Intelligent robotized depalletizer

ABSTRACT

A layer destacking system, for destacking a layer from a stacked layer pallet load, including a layer seating platform configured so as to seat the destacked layer on the layer seating platform, a slip sheet detection sensor arranged to sense a slip sheet in contact with the seated destacked layer, a slip sheet pickup removal mechanism, and a controller that receives a signal from the slip sheet detection sensor identifying presence of the slip sheet. The controller is operably connected to the slip sheet pickup removal mechanism so as to actuate the slip sheet pickup removal mechanism effecting discharge of the slip sheet off the layer seating platform.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a non-provisional of and claims the benefit of U.S.provisional patent application No. 63/270,765 filed on Oct. 22, 2021,the disclosure of which is incorporated herein by reference in itsentirety.

BACKGROUND 1. Field

The disclosed embodiment generally relates to depalletizing, and moreparticularly, to slip sheet detection and removal.

2. Brief Description of Related Developments

The retail distribution of products (whether for conventional “brick andmortar” stores, online stores, or mixed retail channels) demandsimprovements in storage, sortation, and transport efficiencies,particularly for distribution of what is known as mixed cases orheterogeneous cases (within a given transport) whether for storereplenishment or individual orders. The application ofintelligent/adaptive automation thereto has increasingly facilitatedimprovement in efficiency at many levels of distribution includingstorage, sortation and transport.

Distribution centers and warehouses typically receive their productssuch as cases, boxes, open trays, stretch wrapped trays, etc. on astructured pallet, e.g. orderly positioned without gaps between them.Generally slip sheets (thin pallet-sized sheets of material) are placedbetween the pallet layers of the pallet to generally improve stabilityof the pallet load compared to pallet load without slip sheets.Depalletizing systems are known in the art to remove the products fromthe pallet. In some instances the slip sheet is removed with the palletlayer while in other instances the slip sheet remains on the palletafter picking of the pallet layer.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the disclosed embodiment areexplained in the following description, taken in connection with theaccompanying drawings, wherein:

FIG. 1 is a schematic illustration of a warehouse system in accordancewith aspects of the disclosed embodiment;

FIG. 2 is a schematic illustration of a pallet load in accordance withaspects of the disclosed embodiment;

FIG. 3 is a schematic perspective illustration of a bottom slip sheetremoval system of the warehouse system of FIG. 1 in accordance withaspects of the disclosed embodiment;

FIG. 4A is a schematic perspective illustration of a portion of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 4B is a schematic perspective illustration of a portion of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 5A is a schematic perspective illustration of a portion of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 5B is a schematic perspective illustration of a portion of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 5C is a schematic perspective illustration of a portion of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 6 is a schematic plan view of a portion of the bottom slip sheetremoval system of FIG. 3 in accordance with aspects of the disclosedembodiment;

FIG. 7 is a schematic plan view of a portion of the bottom slip sheetremoval system of FIG. 3 in accordance with aspects of the disclosedembodiment;

FIG. 8 is a schematic elevation view of a portion of the bottom slipsheet removal system of FIG. 3 in accordance with aspects of thedisclosed embodiment;

FIG. 9 is a schematic elevation view of a portion of the bottom slipsheet removal system of FIG. 3 in accordance with aspects of thedisclosed embodiment;

FIG. 10 is a schematic elevation view of a portion of the bottom slipsheet removal system of FIG. 3 in accordance with aspects of thedisclosed embodiment;

FIG. 11 is a schematic elevation view of a portion of the bottom slipsheet removal system of FIG. 3 in accordance with aspects of thedisclosed embodiment;

FIG. 12 is a schematic elevation view of a portion of the bottom slipsheet removal system of FIG. 3 in accordance with aspects of thedisclosed embodiment;

FIG. 13 is a schematic elevation view of a portion of the bottom slipsheet removal system of FIG. 3 in accordance with aspects of thedisclosed embodiment;

FIG. 14A is a schematic perspective illustration of a portion of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 14B is a schematic perspective illustration of a portion of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 15A is a schematic perspective illustration of a portion of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 15B is a schematic perspective illustration of a portion of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 16A is a schematic plan view of a portion of the bottom slip sheetremoval system of FIG. 3 in accordance with aspects of the disclosedembodiment;

FIG. 16B is a schematic plan view of a portion of the bottom slip sheetremoval system of FIG. 3 in accordance with aspects of the disclosedembodiment;

FIG. 17A is a schematic plan view of a portion of the bottom slip sheetremoval system of FIG. 3 in accordance with aspects of the disclosedembodiment;

FIG. 17B is a schematic plan view of a portion of the bottom slip sheetremoval system of FIG. 3 in accordance with aspects of the disclosedembodiment;

FIGS. 18A-18C are schematic plots of exemplary sensor signals of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIGS. 18D-18F are schematic plots of exemplary sensor signals of thebottom slip sheet removal system of FIG. 3 in accordance with aspects ofthe disclosed embodiment;

FIG. 19 is an exemplary flow diagram of a method for the bottom slipsheet removal system of FIG. 3 in accordance with aspects of thedisclosed embodiment; and

FIG. 20 is an exemplary flow diagram of a method in accordance withaspects of the disclosed embodiment.

DETAILED DESCRIPTION

FIG. 1 is a schematic illustration of a warehouse system or distributionfacility 100WS (referred to herein as warehouse system 100WS) inaccordance with aspects of the disclosed embodiment. Although theaspects of the disclosed embodiment will be described with reference tothe drawings, it should be understood that the aspects of the disclosedembodiment can be embodied in many forms. In addition, any suitablesize, shape or type of elements or materials could be used. It should beunderstood that while the warehouse system 100WS is described herein asan automated warehouse system the aspects of the disclosed embodimentare also applicable to distribution facilities having any suitabletransport systems, such as both automated and manual transport systemsor to wholly manual transport systems.

Referring to FIGS. 1, 2, and 3 , the aspects of the disclosed embodimentprovide an automatic inbound bottom slip sheet detection and removalsystem 300 (also referred to herein as the slip sheet removal system forconvenience). The slip sheet removal system 300 is configured to receivea pallet layer from a palletizer cell 10 of the warehouse system 100WS.The slip sheet removal system 300 includes an intelligent detectionsystem (as described herein) that is configured to at least detect apresence of a slip sheet 277 (see FIGS. 2, 16A, and 16B) located atleast underneath (i.e., a bottom slip sheet) the pallet layer PL1-PL5(each of pallet layer PL1-PL5 being generally referred to as palletlayer PL). Based on the detected presence of the slip sheet 277 the slipsheet removal system 300 is configured to move the pallet layer PL offof the slip sheet 277 and effect removal of the slip sheet 277 from theslip sheet removal system 300. Here, at least some of the components ofthe slip sheet removal system 300 that effect slip sheet removal areactuated upon detection of the presence of the slip sheet and areotherwise deactivated upon detection of the absence of a slip sheet suchthat feed of subsequent pallet layers along a conveyor of the slip sheetremoval system is unencumbered by any removal of a detected slip sheet.In accordance with the aspects of the disclosed embodiment, the slipsheet removal system 300 may decrease operating costs and may increaseservice life of the slip sheet removal system 300 as the slip sheetremoval components are actuated when a slip sheet is detected and areotherwise deactivated. The slip sheet removal system 300 may alsoprovide compact footprint so that the slip sheet removal system 300 maybe integrated with a conveyor system having commercially availableconveyor sections. The slip sheet removal system 300 may also providefor slip sheet 277 removal with a substantially steady state/continuousconveyance of pallet layers/cases through the slip sheet removal system300.

Referring to FIGS. 1 and 2 , in accordance with the aspects of thedisclosed embodiment, the warehouse system 100WS includes at least onepalletizer/depalletizer cell 10A, 10B (generally referred to herein aspalletizer cell 10). The palletizer cell 10 has one or more robotic casemanipulator(s) 14 (also referred to herein as articulated robots,adaptive real time robots, robots, or product picking apparatus) thatplace (individually or manufactured pickfaces) mixed pallet load articleunits CU (also referred to herein as case units or cases or products 18)in stacks SL1-Sn and/or layers PL1-PL4 building a mixed case pallet loadPAL with vision system assistance. A suitable example of apalletizer/depalletizer is described in U.S. Pat. No. 10,343,857 issuedon Jul. 9, 2019 and titled “Vision-Assisted Robotized Depalletizer”, andin U.S. patent application Ser. No. 17/070,753 filed on Oct. 14, 2020and titled “Vision-assisted Robotized Depalletizer”, the disclosures ofwhich are incorporated herein by reference in their entireties.

Referring again to FIG. 1 , in accordance with aspects of the disclosedembodiment the warehouse system 100WS includes a storage and retrievalsystem 100 that may operate in a retail distribution center or warehouseto, for example, fulfill orders received from retail stores for caseunits. In one example, the case units may be cases or units of goods notstored in trays, on totes or on pallets (e.g., uncontained). In otherexamples, the case units may be cases or units of goods that arecontained in any suitable manner such as in trays, on totes or onpallets. It is noted that the case units may include cased units ofgoods (e.g., case of soup cans, boxes of cereal, etc.) or individualgoods that are adapted to be taken off of or placed on a pallet. Inaccordance with the embodiments, shipping cases for case units (e.g.cartons, barrels, boxes, crates, jugs, or any other suitable device forholding case units) may have variable sizes and may be used to hold caseunits in shipping and may be configured so they are capable of beingpalletized for shipping. It is noted that when, for example, bundles orpallets of case units arrive at the storage and retrieval system thecontent of each pallet may be uniform (e.g., each pallet holds apredetermined number of the same item—one pallet holds soup and anotherpallet holds cereal) and as pallets leave the storage and retrievalsystem the pallets may contain any suitable number and combination ofdifferent case units (e.g., each pallet may hold different types of caseunits —a pallet holds a combination of soup and cereal). In theembodiments the storage and retrieval system described herein may beapplied to any environment in which case units are stored and retrieved.

The storage and retrieval system 100 may be configured for installationin, for example, existing warehouse structures or adapted to newwarehouse structures. In the aspects of the disclosed embodiment, thestorage and retrieval system may include one or more in-feed transferstation 170 and one or more out-feed transfer station 160, in/out caseconveyors 150A, 150B, 150C (generally referred to as in/out caseconveyors 150), a storage structure array 130, and a number ofautonomous vehicular transport robots 110 (referred to herein as“bots”). In the aspects of the disclosed embodiment the storage andretrieval system may also include robot or bot transfer stations, asdescribed in U.S. Pat. No. 9,096,375 issued on Aug. 4, 2015 thedisclosure of which is incorporated by reference herein in its entirety.In the aspects of the disclosed embodiment the bot transfer stations mayprovide an interface between the bots 110 and the in/out case conveyors150 such that case units can be indirectly transferred between the bots110 and the in/out case conveyors 150 through the bot transfer stations.In the aspects of the disclosed embodiment case units may be transferreddirectly between the bots 110 and the in/out case conveyors 150.

The storage structure array 130 may include multiple levels of storagerack modules that form a storage array of storage locations 130SL forcase units, each storage location 130SL of which is arranged for storageof at least one case unit at each storage location 130SL. In one aspect,each level of the storage structure array 130 includes respectivestorage/picking aisles 130A, and transfer decks 130B for transferringcase units between any of the storage areas of the storage structurearray 130 and any shelf of any in/out case conveyors 150. The storageaisles 130A, and transfer decks 130B are also configured to allow thebots 110 to traverse the storage aisles 130A and transfer decks 130B forplacing case units into picking stock and to retrieve ordered caseunits, where the case units are stored or otherwise held in the storageaisles 130A and/or on the transfer deck 130B in storage locations 130SL.The bots 110 may be any suitable bots capable of carrying andtransferring case units throughout the storage and retrieval system 100.Suitable examples of bots can be found in, for exemplary purposes only,U.S. Pat. No. 8,425,173 issued on Apr. 23, 2013, U.S. Pat. No. 9,561,905issued on Feb. 7, 2017, U.S. Pat. No. 8,965,619 issued on Feb. 24, 2015,U.S. Pat. No. 8,696,010 issued on Apr. 15, 2014, U.S. Pat. No. 9,187,244issued on Nov. 17, 2015, United States pre-grant publication number2012/0189416 (U.S. Ser. No. 13/326,952) titled “Automated Bot withTransfer Arm” filed on Dec. 15, 2011, and U.S. Pat. No. 9,499,338 issuedon Nov. 22, 2016, the disclosures of which are incorporated by referenceherein in their entireties. The bots 110 may be configured to place caseunits, such as the above described retail merchandise, into pickingstock in the one or more levels of the storage structure array 130 andthen selectively retrieve ordered case units for shipping the orderedcase units to, for example, a store or other suitable location.

The in-feed transfer stations 170 and out-feed transfer stations 160 mayoperate together with their respective in/out case conveyors 150A, 150Bfor bi-directionally transferring case units to and from one or morelevels of the storage structure array 130 effecting infeed of the caseunits into the storage structure array 130 and output of the case unitsfrom the storage structure array 130. It is noted that while the in-feedtransfer stations 170 and the outfeed transfer stations 160 (and theirrespective in/out case conveyors 150A, 150B and palletizer/depalletizercells 10A, 10B) are described as being dedicated inbound (e.g., in-feed)transfer stations 170 and dedicated outbound (e.g., out-feed) transferstations 160, in the aspects of the disclosed embodiment each of thetransfer stations 170, 160 may be used for both inbound and outboundtransfer of case units from the storage and retrieval system. It isnoted that while in/out case conveyors are described herein, theconveyors may be any suitable conveyors (including any suitabletransport path orientation, such as vertical and/or horizontal conveyorpaths) or transfer/picking devices having any suitable transport pathorientation.

In one aspect, as described above, each of the in-feed transfer stations170 and the out-feed transfer stations 160 include a respective in/outcase conveyor 150A, 150B (at least one of which includes the slip sheetremoval system 300) and a respective palletizer/depalletizer cell 10A,10B (referred to generally herein as palletizer cell 10). In one aspect,the palletizer/depalletizer cells 10 are automated cells each beingconfigured to receive loaded pallets (such as with uniform or mixed caseunits or products) from, for example, a pallet load in area 175 whichmay include an in-out loaded pallet conveyor 175C (illustrated in FIG. 1as an input conveyor) and/or build a loaded pallet (such as with uniformor mixed case units or products) for transport to, for example, a palletload out area 180 which may include an in-out loaded pallet conveyor180C (illustrated in FIG. 1 as an output conveyor). In one aspect, theconveyors 175C, 180C are each connected to the storage structure array130 and are configured so as to bi-directionally transport loadedpallets in an input direction towards the storage structure array 130,and in a different output direction away from the storage structurearray 130. In one aspect, the conveyors 175C, 180C may each include aconveyor arrangement with a distributed conveyor bed arranged to form aconveying path or in other aspects, the conveyors 175C, 180C may bediscrete transport units such as, for example, a fork lift/pallet truck.Suitable examples of automated palletizer/depalletizer cells 10A, 10Bmay be found in U.S. patent application Ser. No. 15/235,254 filed onAug. 12, 2016, and U.S. Pat. No. 8,965,559 issued on Feb. 24, 2015, thedisclosures of which are incorporated herein by reference in theirentireties. Each palletizer cell includes one or more robotic casemanipulators 14, which may also be referred to articulated robots orrobots. The one or more robotic case manipulators 14 are configured, asdescribed herein, so as to transport and place the pallet load articleunits CU serially onto a pallet support so as to build (or in otheraspects as described herein, decompose or decommission) the pallet load250 on a pallet unloading/loading station 301 (see FIG. 3 ).

Where the palletizer cell 10 functions in an output role as apalletizer, pallet load article units CU, that can be of various sizes,arrive at the palletizer cell 10 via the in/out case conveyors 150B, arepicked by one of the robotic case manipulators 14 and placed on thepallet load PAL as will be described herein. Where the palletizer cell10 functions in an output role as a palletizer, a full pallet load PAL(see FIG. 2 ) made from a variety of case units is ready to be picked upby a forklift from the palletizer cell 10 for conveyance to a palletload out 180 area. Where the palletizer/depalletizer cell 10 functionsin an input role as a depalletizer, a full pallet load of cases (whichmay be similar to pallet load PAL and formed of homogenous or mixedcases), made from a variety of pallet load article units CU, disposed inpallet load layers, is transferred to a pallet unloading/loading station301 of the palletizer cell 10 in any suitable manner, such as by a forklift or other conveyance, from a pallet load in 175 area. Each of thepallet load layers PL1, PL2, PL3, PL4, PL5 being formed of more than onecases CU juxtaposed at a common level over an area of the pallet loadPAL. In one aspect, as illustrated in FIG. 2 , the pallet layers may bemixed pallet layers that include cases CU of different sizes; while inother aspects, as illustrated in FIG. 3 , the pallet layers may beuniform layers that include cases CU having substantially the same sizethroughout the pallet layer. The one or more robotic case manipulators14 pick the pallet load article units CU from the pallet PAL fortransfer into the storage structure array 130.

In one aspect, each in-feed transfer station 170 forms, a case inputpath Ip where the palletizer/depalletizer cell 10A depalletizes caseunits, layer by layer, or otherwise depalletizes the case units intosingle case units from standard pallets (e.g., homogenous pallets havinga stability suitable for automatic engagement of a pallet layer by anautomatic layer interface unit, such as the product picking apparatus orrobot 14). The palletizer/depalletizer cell 10A is in communication witha transport system of the automated storage and retrieval system 100,such as an in/out case conveyor 150A so as to form an integral inputsystem (e.g., the in-feed transfer station 170) that feeds case units tothe automated storage and retrieval system 100. Each in-feed transferstation 170 defines the case input path Ip that is integrated with theautomated storage and retrieval system 100 and warehouse managementsystem 199, where the warehouse management system 199 includes anysuitable controller 199C configured with any suitable non-transitoryprogram code and memory to manage, at least, case unit input to thestorage structure array 130, case unit storage distribution within thestorage structure array 130 and case unit retrieval from the storagestructure array 130, case unit inventory/replenishment, and case unitoutput.

In one aspect, each case unit input path Ip includes at least onecorresponding case unit inspection cell 142 in communication with thewarehouse management system 199. In one aspect, the at least onecorresponding case unit inspection cell 142 may be any suitableinspection cell including any suitable volumetric inspection, such aswith a multi-dimensional light curtain, imaging systems and/or any othersuitable sensing/sensor arrangement configured to detect case unitdefects and identify the case units for, e.g., inventory, transportsequencing, storage distribution and sequencing the case unit for outputfrom the storage structure array 130.

In one aspect, as noted above, the palletizer/depalletizer cell 10A maybe fully automatic so as to break down or decommission layer(s) from apallet unloading at the palletizer/depalletizer cell 10A. It is notedthat, referring to FIG. 2 , the term decommission refers to the removalof a pallet layer PL1, PL2, PL3, PL4 (in whole or in part) from a palletPAL so that each pallet load article unit CU is removed from the layerPL1, PL2, PL3, PL4 at a predetermined level 200 (which may correspond toa decommissioning/commissioning level or transfer plane) of the palletPAL so that, in some aspects, the pallet PAL is indexed (by any suitablepallet lifting device of the palletizer cell 10) to a next level of thepallet PAL for removal of the next layer PL2, PL3 (in whole or in part)corresponding to the next level of the pallet PAL.

In one aspect, the palletizer/depalletizer cell 10A is configured todecommission the layers PL1, PL2, PL3, PL4 so that the decommissioningis synchronous or otherwise harmonized by (e.g., matched with) thewarehouse management system 199 with a predetermined rate of case unitflow or feed rate, established by the warehouse management system 199,in the automated storage and retrieval system 100. For example, in oneaspect, the warehouse management system 199 is configured to set and/ormonitor a predetermined rate of case unit flow within the automatedstorage and retrieval system 100. For example, the warehouse managementsystem 199 monitors and manages the automated systems of the automatedstorage and retrieval system 100 (such as, e.g., the in/out caseconveyors 150A, 150B, bots 110 and palletizer/depalletizer cells 10A,10B), where each of the automated systems, or one or more of automatedsystems have a given transaction time (such as a time/period to effect abasic unit of transport or transfer of cases, e.g. to transfer a caseunit on/off the in/out case conveyor to a pick/place station, or lift acase unit a predetermined distance, or bot transfer pick/place on astorage location, a time to transfer a pallet layer to or from a pallet,etc.) that in effect, singularly or in combination define, under controlof the warehouse management system 199 or any other suitable controllerof the automated storage and retrieval system 100 (e.g., botcontrollers, conveyor controllers, palletizer/depalletizer controllers,etc.), the predetermined rate of case unit flow in the automated storageand retrieval system 100 established by the warehouse management system199. For example, the controller 199C of the warehouse management system199 is communicably connected to the in-out case conveyor(s) 150A, 150Bso that the in-out case conveyor(s) 150A, 150B bi-directionallytransport the case units to and from the storage structure array 130 ata predetermined case feed rate. The controller 199C may also becommunicably connected to a palletizer-depalletizer cell 10A, 10Bcorresponding to the in-out case conveyor(s) 150A, 150B so that thelayer commissioning and decommissioning of the palletizer/depalletizercell 10A, 10B, which are respectively substantially continuous, matchesthe predetermined case feed rate. While the aspects of the disclosedembodiment are described herein with respect to a warehouse system 100WShaving automated storage and retrieval system 100 with automatedtransport systems, the aspects of the disclosed embodiment are alsoapplicable to distribution facilities having any suitable transportsystems such as both automated and manual transport systems or to whollymanual transport systems, where both the automated transporttransactions and the manual transport transactions each have respectivetransaction times where the commissioning and decommissioning of caseunits to and from pallets may be matched to the transaction times in amanner substantially similar to that described herein.

In one aspect, each out-feed transfer station 160 forms, a case outputpath Op where the palletizer/depalletizer cell 10B palletizes caseunits, layer by layer onto pallets PAL such as with an automatic layerinterface unit, such as the one or more robotic case manipulators 14. Inone aspect, the pallets PAL may be formed as standard pallets (e.g.homogeneous case units) or as mixed pallets, such as described in U.S.patent application Ser. No. 14/997,920 filed on Jan. 18, 2016 thedisclosure of which is incorporated herein by reference in its entirety.In one aspect, the warehouse management system 199 is configured toestablish a pallet solution, with mixed case units, that provides astable pallet load stack suitable for an end effector of the one or morerobotic case manipulators 14 to transfer as a layer. As described above,a suitable example, of the palletizer/depalletizer cell 10B may be foundin U.S. patent application Ser. No. 15/235,254 filed on Aug. 12, 2016,the disclosure or which was previously incorporated herein by referencein its entirety.

In one aspect, the palletizer/depalletizer cell 10B is in communicationwith a transport system of the automated storage and retrieval system100, such as an in/out case conveyor 150B so as to form an integraloutput system (e.g., the out-feed transfer station 160) that receivescase units from the automated storage and retrieval system 100 forplacement on pallets according to any suitable case out order sequence.For example, as described above, pallet load article units or cases CUrouted to the one or more robotic case manipulators 14 are transferredto the pallet PAL by the end effector of the one or more robotic casemanipulators 14, with the pallet load article units CU (output caseunits) being arranged in a predetermined sequence established by thewarehouse management system 199, layer by layer (noting that the layermay cover the pallet in whole or in part) to form a standard outputpallet load.

Each out-feed transfer station 160 defines the case output path Op thatis integrated with the automated storage and retrieval system 100 andwarehouse management system 199, where the warehouse management system199 includes any suitable controller 199C configured with any suitablenon-transitory program code and memory to manage the operation of thewarehouse system 100WS, including case unit output from the storagestructure array 130, as described herein. In one aspect, each case unitoutput path Op includes at least one corresponding case unit inspectioncell 142 (as described above) in communication with the warehousemanagement system 199. In one aspect, as noted above, thepalletizer/depalletizer cell 10B may be fully automatic so as to buildor commission layer(s) to a pallet loading at thepalletizer/depalletizer cell 10B. It is noted that, referring to FIG. 2, the term commission refers to the construction of a pallet layer PL1,PL2, PL3, PL4 (in whole or in part) to a pallet PAL so that each palletload article unit CU is inserted to the layer PL1, PL2, PL3, PL4 at apredetermined level 200 (which may correspond to adecommissioning/commissioning level or transfer plane) of the pallet PALuntil the pallet layer PL1, PL2, PL3, PL4, PL5 is formed so that, insome aspect, the pallet PAL is indexed (by any suitable pallet liftingdevice of the palletizer cell 10) to a next level of the pallet PAL forbuilding of the next layer PL1, PL2 (in whole or in part) correspondingto the next level of the pallet PAL. In one aspect, thepalletizer/depalletizer cell 10B is configured to commission the layersPL1, PL2, PL3, PL4, PL5 so that the commissioning is synchronous orotherwise harmonized (e.g. matched with) by the warehouse managementsystem 199 with a predetermined rate of case unit flow or feed rate,established by the warehouse management system 199, in the automatedstorage and retrieval system 100 in a manner substantially similar tothat described above with respect to the decommissioning of the layersPL1, PL2, PL3, PL4 where the warehouse management system 199 managescase unit retrieval order and the sequence of mixed case unit output toloadout sequence of the mixed case unit pallet load, and otherassociated aspects of output such as inventory reconciliation.

In accordance with aspects of the disclosed embodiment, and referring toFIGS. 1 and 3 , the slip sheet removal system 300 forms a part of arespective in/out case conveyor 150 and includes a controller 333, atleast a bottom slip sheet remover 310, and an intelligent detectionsystem (as described herein). The slip sheet removal system 300 may alsoinclude one or more of a layer place conveyor 320 (also referred to as alayer seating platform), an accumulation conveyor 325 (of which thebottom slip sheet remover 310 is a part), a spreader conveyor 330, and aslip sheet remover 350. Here, the palletizer/depalletizer 10 and theslip sheet removal system 300 may be referred to as an intelligentrobotized depalletizer or layer destacking system LDS (see FIG. 1 notingthe layer destacking system LDS is schematically illustrated and whereone or more in-feed transfer stations 170 include the layer destackingsystem LDS as illustrated. As described herein, the slip sheet removalsystem 300 provides intelligence to discriminate picking (and removing)a top slip sheet and a bottom slip sheet. The controller 333 iscommunicably coupled to the accumulation conveyor 325 (and the bottomslip sheet remover 310 thereof), the layer place conveyor 320, thespreader conveyor 330, and the slip sheet remover 350 (e.g., thecontroller 333 is connected the respective components, e.g., motors,sensors, scanners, vision systems, etc. of the slip sheet removal system300) to effect operation of the slip sheet removal system 300 in themanner described herein.

As described herein, the slip sheet removal system 300 includes a slipsheet detection sensor (formed by one or more of the sensors, scanners,vision systems, etc. thereof) and the controller 333 is communicablycoupled to the slip sheet detection sensor so as to receive a signalfrom the slip sheet detection sensor identifying presence of a slipsheet 277 (as described herein). The controller 333 is configured todetermine from the received signal the slip sheet 277 contacting atleast one of an uppermost surface PLUS and a bottom surface PLLS (see,e.g., FIG. 15B) of the seated pallet layer PL. The controller 333 is anysuitable controller (with any suitable memory and processor) and in someaspects may be incorporated into the controller 199C or is otherwise incommunication with at least controller 199C and/or a controller 10C of acorresponding palletizer/depalletizer cell 10A, 10B that conveys casesCU to or receives cases CU from the slip sheet removal system 300.

Referring to FIGS. 1, 3, 4A, 4B, 6, and 7 , the accumulation conveyor325 and layer place conveyor 320 are illustrated as having a commonframe 498B; however, in other aspects the accumulation conveyor 325 andlayer place conveyor 320 may have separate frames that are coupled toeach other in any suitable manner to form frame 498B. The frame 498B isa portion of a frame 498 of the slip sheet removal system 300. The layerplace conveyor 320 is configured to receive pallet layers PL from anysuitable robotic case manipulator(s) 14 of the respective palletizercell 10. The layer place conveyor 320 includes a mat top conveyor belt321 having a conveying surface 321CS. Here, the layer place conveyor 320is configured so as to seat the placed pallet layer PL (also referred toas a destacked layer) on the conveyance surface 321CS of the mat topconveyor belt 321. The mat top conveyor belt 321 has a conveyancetraverse direction (e.g., direction 499) that traverses the seatedpallet layer PL off of the layer place conveyor 320 (see FIGS. 3 and16A-17B). For example, the mat top conveyor belt 321 is driven by anysuitable motors to convey the placed pallet layer PL (i.e., seated onthe mat top conveyor belt 321) in the conveyance direction 499A fortransferring the pallet layer PL (and the cases CU thereof) to theaccumulation conveyor 325 (see FIGS. 16A-17B). The accumulation conveyor325 includes a mat top conveyor belt 326 having a conveying surface326CS, where the mat top conveyor belt is driven by any suitable motorsto convey the seated pallet layer PL (i.e., seated on the conveyingsurface 326CS) in the conveyance direction 499 for transferring theseated pallet layer PL (and the cases CU thereof) to the bottom slipsheet remover 310. The mat top conveyor belt 321 of the layer placeconveyor 320 is driven at a lower speed than the mat top conveyor of the326 of the accumulation conveyor 325 so that, without the presence of aslip sheet 277 underneath the seated pallet layer PL, the cases CU ofthe seated pallet layer are spaced apart from each other by a distance1700 (see FIG. 17 ) in/along the conveyance direction 499 withtransition of adjacent cases from the layer place conveyor 320 to theaccumulation conveyor 325.

Referring to FIGS. 3, 4A, 4B, 5A, 5B, 5C, 14A, 14B, 15A, and 15B, thebottom slip sheet remover 310 includes a frame 498A, a conveyor portion400 (which is a portion of the accumulation conveyor 325), a pusher 420(also referred to as displacer 420, see FIGS. 3, 4A and 4B), and atleast a portion of the intelligent detection system (e.g., such as aslip sheet detector 1400, which forms what may be referred to as a slipsheet detection sensor). The frame 498A of the bottom slip sheet remover310 is another portion of the frame 498 of the slip sheet removal system300 and is coupled to the frame 498B in any suitable manner. Theconveyor portion 400 (which may be substantially similar to mat topconveyors 321, 326) is coupled to the frame 498A in any suitable manner(or is otherwise integrally formed with the frame 498A) and isconfigured to transport the seated pallet layer PL (and the cases CUthereof—see FIGS. 16A-17B) generally along a conveyance direction 499(noting that the direction 499A corresponds with the respective in/outcase conveyor 150 operating in an inbound role and the direction may bereversed, see direction 499B, with the respective in/out case conveyor150 operating in an outbound role). The conveyor portion 400 includesany suitable conveyance surface(s) 401 configured with a substantiallyuniform (e.g., common or steady state) coefficient of friction foreffecting at least conveyance of the pallet layer PL along theconveyance direction 499. For example, as illustrated in FIG. 5A theconveyance surface 401 is formed by a substantially continuous/solidrubber top (endless) belt 401R. As another example, as illustrated inFIG. 5B the conveyance surface 401 is formed by a perforated rubber top(endless) belt 401P. As yet another example, the conveyance surface(s)401 is/are formed of more than one rubber top (endless) belt 401C (e.g.,cassette style conveyor sections). While the conveyor tops are describedherein as being rubber in other aspects the conveyor tops may be formedof any suitable material having a coefficient of friction that effectsboth conveyance of the pallet layer PL and retention of a slip sheet 277in the manner described herein for slip sheet 277 removal. The conveyorportion 400 includes any suitable motor 401M configured to drive theconveyance surface 401 to effect conveyance of the pallet layer PL (andthe cases CU thereof) at least along the conveyance direction 499. Ascan be seen in FIGS. 5A, 5B, and 5C the motor 401M includes any suitablelock 401L configured to arrest motion of the conveyance surface 401 inthe conveyance direction 499 and hold the conveyance surface 401substantially stationary relative to the conveyance direction 499. Thelock 401L may be configured as a friction brake (e.g., clutch brake,etc.), magnetic brake (e.g., eddy current magnetic brake, etc.), or anyother suitable brake configured to arrest and maintain substantiallystationary the conveyance surface 401.

As can be seen in FIGS. 3, 4A, and 4B the pusher or displacer 420 ismovably coupled to the layer place conveyor 320 and, as describedherein, is actuable in a direction that is aligned with the conveyancetraverse direction 499. As described herein the displacer is actuablebetween an advanced position (see FIGS. 16B and 17B) and a retractedposition (see FIGS. 3, 16A, and 17A) that displaces the pallet layer PLand the slip sheet 277 on the bottom surface of the pallet layerrelative to each other (as described herein) stripping the pallet layerPL and slip sheet 277 from each other. The pusher 420 includes at leastone traverser 430, each traverser 430 having a linear actuator 430L, acarriage 430C coupled to the linear actuator 430L, and a pusher bar 435pivotally coupled to the carriage 430C so as to be actuable to raise andlower to and from an engaged or deployed position (see, e.g., FIGS. 4A,4B, and 8 ) and a disengaged or retracted position (see, e.g., FIGS. 3,9, 10, and 13 ) as described herein. The linear actuator 430L is coupledto and extends along the frame 498A in a direction substantiallyparallel with the conveyance direction 499. The linear actuator 430L isany suitable linear actuator (e.g., hydraulic or pneumatic cylinder,electric drive, belt/chain drive, gear drive, etc.) configured to movethe carriage 430C along the frame 498A in conveyance directions 499A,499B in a reciprocating movement. The pusher bar 435 is pivotallycoupled to the carriage 430C so as to move as a unit with the carriage430C along the conveyance direction 499. The carriage 430C includes anysuitable drive (e.g., motor, actuator, transmission, etc.) 430CDconnected to the pusher bar 435 and configured to pivot the pusher barin direction 495 between the deployed position (illustrated in FIGS. 4A,4B, and 8 ) and the retracted position (illustrated in FIGS. 3, 9, 10,and 13 ). With the pusher bar 435 in the retracted position, the palletlayer PL is conveyed by and between the accumulation conveyor 325 andthe conveyor portion 400 of the bottom slip sheet remover 310 along theconveyance direction 499 (and by and between the conveyor portion 400 ofthe bottom slip sheet remover 310 and the spreader conveyor 330 inconveyance direction 499). With the pusher bar 435 in the deployedposition, the pusher bar 435 (with actuation of the linear actuator430L) pushes the pallet layer from the conveyor portion 400 of thebottom slip sheet remover 310 (with the conveyor portion 400 heldstationary) in the conveyance direction 499A to effect removal of a slipsheet 277 in the manner described herein, such as by moving the palletlayer PL and slip sheet 277 relative to each other to strip the palletlayer PL off of the slip sheet 277.

In the aspect illustrated in FIG. 4A the bottom slip sheet remover 310includes two traversers 430 (e.g., one traverser on each lateral sideLAT1, LAT2 of the bottom slip sheet remover 310). Each traverser 430includes a respective pusher bar 435 that spans about half the width(e.g., the width of the conveyor portion 400 between the lateral sidesLAT1, LAT2) of the conveyor portion 400 so that the combined span of therespective pusher bars 435 spans across the pallet layer PL for pushingthe pallet layer, in its entirety, from the conveyor portion 400 asdescribed herein. Here, the bottom slip sheet remover 310 illustrated inFIG. 4A includes two opposing pusher bars 435 that are operated in acoordinated manner (e.g., the traversers 430 rotate the respectivepusher bars 435 to the deployed position and move the pusher bars 435substantially simultaneously at the same rate of movement in direction499A) to collectively push a pallet layer PL from the conveyor portion400 of the accumulator conveyor 325 to the spreader conveyor 330.

In the aspect illustrated in FIG. 4B the bottom slip sheet remover 310includes one traverser 430 on a lateral side (e.g., either of lateralside LAT1 or lateral side LAT2) of the bottom slip sheet remover 310.The traverser 430 includes a respective pusher bar 435 that spans aboutthe entire width (e.g., the width of the conveyor portion 400 betweenthe lateral sides LAT1, LAT2) of the conveyor portion 400 so that thespan of the respective pusher bar 435 spans across the pallet layer PLfor pushing the pallet layer, in its entirety, from the conveyor portion400 as described herein. Here, the bottom slip sheet remover 310illustrated in FIG. 4B includes a single pusher bar 435 that is operated(e.g., the traverser 430 rotates the respective pusher bar 435 to thedeployed position and moves the pusher bar 435 in direction 499A) topush a pallet layer PL from the conveyor portion 400 of the accumulatorconveyor 325 to the spreader conveyor 330.

While one pusher bar 435 or two pusher bars 435 are illustrated in thefigures it should be understood that the bottom slip sheet remover mayhave more than two pusher bars.

As can be seen best in FIGS. 14A, 14B, 15A, 15B, and as noted above, thebottom slip sheet remover 310 includes a portion of the intelligentdetection system of the slip sheet removal system 300. The portion ofthe intelligent detection system included with the bottom slip sheetremover 310 is the slip sheet detector 1400. As described herein, theslip sheet detector 1400 is coupled to the layer place conveyor 320 andarranged to sense a slip sheet 277 in contact with the seated palletlayer PL on at least one of an uppermost surface PLUS and a bottomsurface PLLS of the seated pallet layer (see FIG. 15B where the palletlayer PL is illustrated without a slip sheet for illustrative purposesonly). Here, the slip sheet detector 1400 is disposed (as describedherein) to sense the slip sheet 277 on the at least one of the uppermostsurface PLUS and the bottom surface PLLS of the seated pallet layer PL.As described herein, the slip sheet detector 1400 is disposed to sensethe slip sheet 277 on the at least one of the uppermost surface PLUS andthe bottom surface PLLS of the seated pallet layer PL with the palletlayer PL seated on the conveying surface (e.g., one or more of conveyingsurfaces 321CS, 326CS, 401) of the layer place conveyor 320.

The slip sheet detector 1400 includes a sub-frame 498S, a scanner 1405,and a mirror 1410 (e.g., an optical mirror or other suitablemirror/reflective surface). The sub-frame 498S is configured forcoupling with the frame 498 of the bottom slip sheet remover 310;however, in other aspects the sub-frame 498S may be configured forcoupling with a frame 498B of the accumulator conveyor 325/layer placeconveyor 320. The scanner 1405 is any suitable scanner/sensor configuredwith a substantially planar field of view FOVS that can be extendedthrough a gap 485 formed in the accumulation conveyor 325 between theconveyance surface 401 of conveyor portion 400 of the bottom slip sheetremover 310 and the mat top conveyor belt 326 so as to detect spaces(e.g., distance 1700) between adjacent cases CU (see FIG. 17A). As anexample the scanner 1405 is an electromagnetic beam sensor arranged soas to emit a sensing beam (see, e.g., FIG. 15A) in a direction thatcrosses a seating plane SP (see FIG. 15B) of the conveying surface321CS, 326CS, 401 so as to sense the slip sheet 277 on the at least oneof the uppermost surface PLUS and the bottom surface PLLS of the seatedpallet layer PL. As another example, the scanner 1405 is an imagingsensor (e.g., two dimensional presence sensors such as ranging laserscanners, LIDAR scanners, two-dimensional ranging opticalscanners/sensors, sonic ranging sensors, time-of-flight cameras, etc.)registering (e.g., in any suitable memory, such as of controller 333 orother suitable controller) the slip sheet 277 on the at least one of theuppermost surface PLUS and the bottom surface PLLS of the seated palletlayer PL in the direction crossing the seating plane SP of the seatedpallet layer PL seated on the conveying surface 321CS, 326CS, 401. Thescanner 1405 may be any suitable electromagnetic beam scanner or othersuitable optical scanner.

The scanner 1405 is coupled to the sub-frame 498S by an adjustable mount1450; however, in other aspects the scanner 1405 may be fixed to thesub-frame 498S in any suitable manner. The adjustable mount 1450includes at least one stage of adjustment, such as in one or more of theX, Y, Z, Rx, Ry, and Rz directions. The Y direction is substantiallycoincident with e.g., substantially parallel with) the conveyancedirection (also referred to as conveyance traverse direction) 499, the Xdirection is transverse to (e.g., substantially perpendicular to) theconveyance direction 499 within a plane defined by the conveyancesurface 401, and the Z direction is transverse to the conveyancedirection 499 and is substantially perpendicular to the plane defined bythe conveyance surface 401. R_(X), R_(Y), and R_(Z) are respectivelyrotation directions about the X, Y, and Z axes (see FIGS. 3, 14A, 14B,and 15B). As an example, the adjustable mount 1450 includes a Z axisstage 1450Z (e.g., rack and pinion, ball screw, or other linear/rotaryactuator) configured to raise or lower the scanner 1405 along the Zaxis. The adjustable mount 1450 may also include an X axis stage 1450X(e.g., jack screw or other linear/rotary actuator) configured to tiltthe scanner about the X axis in direction R_(X). The adjustable mount1450 may also include a Y axis stage 1450Y (e.g., jack screw or otherlinear/rotary actuator) configured to tilt the scanner about the Y axisin direction R_(Y).

The mirror 1410 is coupled to the sub-frame 498S so as to reflect/changea direction of radiation (and the field of view FOVS defined thereby)emitted from the scanner 1405, or in other aspects, reflect/change thefield of view FOVS/radiation of any other suitable imaging sensor suchas those described herein. Here, the radiation (and/or field of view)extends from the scanner 1405 and is redirected by the mirror 1410through the gap 485 to the slip sheet 277 or cases CU where theradiation is then reflected by the slip sheet 277 or cases CU backthrough the gap 485 and is redirected by the mirror 1410 to the scanner1405. The mirror 1410 may be fixedly coupled to the sub-frame 498S andthe sub-frame 498S is positioned on the one of frame 498A, 498B so thatthe mirror is aligned with the gap 485 for redirecting the radiationfrom the scanner through the gap 485. In one or more aspects the mirror1410 may be mounted to the sub-frame 498S about a pivot axis 1411 sothat the position of the mirror 1410 in direction R_(X1) may be adjustedto effect the return of the radiation from the slip sheet 277 or casesCU to the scanner 1405.

One or more air knives 1460, 1461 are mounted to the sub-frame 498S inany suitable manner and are configured for cleaning a reflective surfaceof the mirror 1410 (i.e., the surface of the mirror that redirects theradiation from/to the scanner 1405) and a lens of the scanner 1405(i.e., the radiation being emitted from and received through the lens).The air knife 1460 is coupled to the sub-frame 498S adjacent the scanner1405 and extends adjacent at least a portion of the scanner 1405 toeject a stream of compressed air across the lens to clean the lens. Theair knife 1461 is coupled to the sub-frame 498S adjacent the mirror 1410and extends adjacent at least a portion of the mirror 1410 to eject astream of compressed air across the mirror 1410 to clean the reflectivesurface. In other aspects, the mirror 1410 may be manually cleaned inany suitable manner. The air knives 1460, 1461 may be activated at thesame time or at different times and at any suitable time intervalsbetween activations. The activation of each air knife 1460, 1461 may befor any suitable duration that effects cleaning of a respective one ofthe reflective surface and lens.

One or more presence sensors 476, 477 are coupled to the frame 498B inany suitable manner and may also form a part of the intelligentdetection system of the bottom slip sheet removal system 300. While theone or more presence sensors 476, 477 are illustrated as being coupledto the frame 498B, in other aspects at least one of the one or morepresence sensors 476, 477 may be coupled to frame 498A, 498B of thebottom slip sheet remover 310 in any suitable manner. The presencesensors 476, 477 may be any suitable two dimensional presence sensorssuch as ranging laser scanners, LIDAR scanners, two-dimensional rangingoptical scanners/sensors, sonic ranging sensors, time-of-flight cameras,etc.

The sensor 477 is coupled to the frame 498B (or frame 498A) and ispositioned relative to both the accumulation conveyor 325 and layerplace conveyor 320 so that a field of view FOVL of the sensor 477 coverssubstantially the entirety of the conveying surface of both theaccumulation conveyor 325 and layer place conveyor 320. Here, the sensor477 provides sensor signals to the controller 333 (which may be conveyedto the controller 10C of the palletizer cell 10), where the sensorsignals indicate a presence or absence of items on the mat top conveyorbelts 321, 326 that may otherwise prevent/obstruct placement of a palletlayer PL by one or more robotic case manipulator(s) 14 of the palletizercell 10. With the mat top conveyor belts 321, 326 substantially free ofobstructions the one or more robotic case manipulator(s) 14 place palletlayers PL to the layer place conveyor 320.

The field of view FOVL of the sensor 477 may include one or morevalidation zones V1, V2 (e.g., see FIG. 6 ) for a self-alignment checkof the presence sensor 477 relative to the X and Y axes. For example,the robotic case manipulator(s) 14 riser/support 14R (shown in thefigures with an exemplary configuration but may have any suitableconfiguration) includes at least two targets 14T1, 14T2 (e.g., see FIG.6 ) that are disposed in a known position relative to the frame 498 andthe presence sensor 477 (it is noted that the field of view of sensor477 (and sensor 476) may extend beyond what is shown in the figures todetect the location of targets disposed on the risers in a mannersimilar to that described herein and the fields of view and targetpositions shown in the figures is for illustrative purposes only). Wherea position of each of the targets 14T1, 14T2 detected by the presencesensor 477 is located in a respective one of the validation zones V1, V2(e.g., within a predetermined tolerance) alignment of the presencesensor 477 is validated. Where the position of one or more of thetargets 14T1, 14T2 detected by the presence sensor 477 is locatedoutside a respective one of the validation zones V1, V2 theself-alignment check is failed and the controller 333 may provide anindication (e.g., visual, aural, etc.) to a human operator that at leastthe presence sensor 477 should be serviced. In other aspects, thetargets 14T1, 14T2 may be located in any suitable location, such as onthe frame 498 of the slip sheet removal system 300.

The sensor 476 is coupled to the frame 498B (or frame 498A) and ispositioned relative to a conveyor of the bottom slip sheet remover 310so that a field of view FOVP of the sensor 476 extends over at least anarea DA (see also FIG. 10 ) of the conveyor portion 400 at which the atleast one pusher bar 435 is rotated to the deployed position. Here, thesensor 476 provides sensor signals to the controller 333 (which may beconveyed to the controller 10C of the palletizer cell 10), where thesensor signals indicate a presence or absence of items on the conveyorportion 400 that may otherwise prevent deployment of the at least onepusher bar 435. With no items present in at least the area DA of theconveyor portion 400 the at least one pusher bar 435 is rotated to thedeployed position. The field of view FOVP of the sensor 476 may includeone or more validation zones V3, V4 (e.g., see FIG. 7 ) for aself-alignment check of the presence sensor 476 relative to the X and Yaxes. For example, the robotic case manipulator(s) 14 riser 14R includesat least two targets 14T3, 14T4 (e.g., see FIG. 7 ) that are disposed ina known position relative to the frame 498 and the presence sensor 476.Where a position of each of the targets 14T3, 14T4 detected by thepresence sensor 476 is located in a respective one of the validationzones V3, V4 (e.g., within a predetermined tolerance) alignment of thepresence sensor 476 is validated. Where the position of one or more ofthe targets 14T3, 14T4 detected by the presence sensor 476 is locatedoutside a respective one of the validation zones V3, V4 theself-alignment check is failed and the controller 333 may provide anindication (e.g., visual, aural, etc.) to a human operator that at leastthe presence sensor 476 should be serviced. In other aspects, thetargets 14T3, 14T4 may be located in any suitable location, such as onthe frame 498 of the slip sheet removal system 300.

The spreader conveyor 330 includes a frame 498C (e.g., see FIGS. 3 and5A-5C) that forms part of the frame 498 of the slip sheet removal system300. The frame 498C is coupled to the frame 498A in any suitable mannerso as to position the spreader conveyor 330 adjacent the bottom slipsheet remover 310. The spreader conveyor 330 includes cassette styleconveyor sections 331. Each cassette style conveyor section 331 includesa mat top conveyor belt 331B. The cassette style conveyor sections 331are angled relative to each so that as cases CU travel along thespreader conveyor 330 in the conveyance direction 499A the cassettestyle conveyor sections 331 spread (i.e., increase the distance between)the cases CU away from each other in the X direction (i.e., in adirection transverse to the conveyance direction 499A) as illustrated inFIGS. 16B and 17B. The cassette style conveyor sections 331 may also beoperated by, e.g., controller 333 (e.g., see FIG. 3 ) so that the mattop conveyor belts 331B of the cassette style conveyor sections 331operate at a faster rate/speed compared to the conveyor portion 400 ofthe bottom slip sheet remover 310 to that a distance or gap 1600 betweencase units CU in the Y direction is increased in a manner substantiallysimilar to that described herein with respect to the transition of casesCU between the layer place conveyor 320 and the accumulator conveyor325. As with the bottom slip sheet remover 310, the accumulator conveyor325, and the layer place conveyor 320, the spreader conveyor 330 mayalso operate to convey the cases CU in direction 499B such that thecases CU flow in direction 499B in a manner substantially opposite tothat described above.

Referring to FIGS. 3, 16A, and 16B, as described above, the slip sheetremoval system 300 may include a slip sheet remover 350 (also referredto as slip sheet pickup removal mechanism 350). The controller 333 isoperably connected to the slip sheet remover 350 so as to actuate theslip sheet remover 350 engaging the slip sheet 277, with the slip sheetcontacting the at least one of the uppermost surface PLUS and the bottomsurface PLLS, and lifting the slip sheet 277 effecting discharge of theslip sheet off the accumulator conveyor 325 (also referred to as a layerseating platform). The actuation of the slip sheet remover 350 (asdescribed herein) is based on the signal received from the slip sheetdetection sensor.

The slip sheet remover 350 extends at least in part over the layer placeconveyor 320 and is configured so as to engage, above the layer placeconveyor 320, the slip sheet 277 contacting the at least one of theuppermost surface PLUS and the bottom surface PLLS of the seated palletlayer PL. The slip sheet remover 350 is disposed at least partiallyabove the bottom slip sheet remover 310 and includes a slip sheetgripper 351 (also referred to as pick head 351) configured to grip orotherwise engage an upper surface 277US of a slip sheet 277 held on theconveyor portion 400 of the accumulator conveyor 325 (or on theuppermost surface PLUS of the pallet layer PL—noting upper surface 277UCis shown in FIGS. 16A and 16B as being underneath the pallet layer PLbut may otherwise be on the uppermost surface PLUS of the pallet layerPL as described herein) and transport the gripped slip sheet 277 to anysuitable slip sheet receptacle 1666 (e.g., bin, pallet, etc.). The slipsheet remover 350 includes a frame 355 configured to movably suspend theslip sheet gripper 351 above the conveyor portion 400. For example, theframe includes one or more stanchions/supports 356 that extend from afloor of a warehouse facility in which the warehouse system 100WS isdisposed. The stanchions 356 support an overhead gantry 370 that carriesthe slip sheet gripper 351. While the overhead gantry 370 is describedas being supported by stanchions 356 in other aspects the overheadgantry 370 may be suspended from a ceiling of the warehouse facility.

The overhead gantry 370 includes at least one horizontal traverse axisand a vertical traverse axis. The at least one horizontal traverse axisincludes any suitable linear actuator 371L (e.g., piston, belt drive,chain drive, etc.) configured to move a gantry carriage 371 (of the slipsheet remover 350) along the X direction. The gantry carriage 371includes any suitable linear actuator 372L (similar to those describedherein) configured to move a Z-axis carriage 372 along the Z direction.The Z-axis carriage 372 is carried by and moves with the gantry carriage371 as a unit along the X direction. The slip sheet gripper 351 iscarried by the Z-axis carriage 372 so that a combination of the gantrycarriage 371 and the Z-axis carriage 372 provide the slip sheet gripper351 with at least two degrees of freedom movement (e.g., in the X and Zdirections).

In some aspects, the Z-axis carriage 372 may include any suitable linearactuator 373L (similar to those described herein) and a Y axis carriage373. The Y axis carriage 373 is moved by the linear actuator along the Yaxis to provide the slip sheet gripper 351 with a third degree offreedom movement.

The slip sheet remover 350 is coupled to the controller 333 so that theslip sheet gripper 351 is moved along one or more of the X, Y, and Zaxes to pick a slip sheet 277 (e.g., see FIG. 16B) from the conveyorportion 400 of the accumulator conveyor 325 and transport the slip sheet277 to the slip sheet receptacle 1666 to effect automatic removal of theslip sheet 277 from underneath the pallet layer PL as described herein.Here, a direction in which the slip sheet remover 350 moves (e.g., atravel path TRVLP—see FIG. 16B for an exemplary travel path although anysuitable path may be followed) is such that layer place conveyor 320feed of a next or subsequent pallet layer is unencumbered as will bedescribed herein.

The slip sheet gripper 351 is configured as a vacuum gripper thatincludes suction holes or cups 387 that releasably grip (e.g., undercontrol of controller 333) the slip sheet 277. A vacuum source 388 forthe suction holes or cups 387 may be disposed on the slip sheet gripper351 or supported on one of the frame 355, the Z-axis carriage 372, andthe Y axis carriage 373 and be communicably coupled to the suction holesor cups 387 in any suitable manner. In other aspects the slip sheetgripper 351 is configured to grip and release a slip sheet 277 in anysuitable manner.

In other aspects, the slip sheet 277 may be manually removed from theconveyor portion 400. In still other aspects, the slip sheet 277 may beautomatically removed from the conveyor portion 400 by redirecting theslip sheet 277 through a gap 390 (see FIG. 3 ) between the conveyorportion 400 of the accumulator conveyor 325 and the mat top conveyorbelts 331B of the spreader conveyor 330 in any suitable manner such asin a manner similar to that described in U.S. patent application Ser.No. 17/070,753 filed on Oct. 14, 2020 and titled “Vision-assistedRobotized Depalletizer”, the disclosure of which was previouslyincorporated herein by reference in its entirety.

Referring to FIGS. 3 and 8-13 , in operation the at least one pusher bar435 of the bottom slip sheet remover 310 has several operatingpositions. At startup/initialization of the bottom slip sheet remover310 the push face PF (see also FIGS. 4A and 4B) of the pusher bar 435 ismoved to a homing position (see FIG. 8 ) where the homing position is apredetermined distance Y1 relative to a datum plane DP of the frame498A. While the at least one pusher bar 435 is shown as being in thedeployed position while at the homing position, the at least one pusherbar 435 may be in the retracted position while at the homing position.The datum plane DP may correspond with a start point/location of travelof cases CU on the bottom slip sheet remover 310 (e.g., the “infeededge” of the conveyor portion 400 or location where the cases firstengage the conveyor portion 400 for conveyance by the bottom slip sheetremover 310). The predetermined distance Y1 may correspond with an endpoint/location of travel of cases CU on the bottom slip sheet remover310 (e.g., the location where the cases disengage the conveyor portion400 from conveyance by the bottom slip sheet remover 310). The locationof the homing position may be defined by a stop surface 801 disposed ata predetermined location on the frame 498A relative to the datum planeDP. Here, the carriage 430C includes a stop surface 802 that has a knownpositional relationship with the push face PF. The carriage is driven inthe conveyance direction 499A to engage the stop surface 801 whereengagement between the surfaces 801, 802 is detected in any suitablemanner (e.g., such as with force feedback, motor current measurement,proximity sensors, etc.). With the surfaces 801, 802 engaged (e.g., insubstantial contact) the push face PF of the at least one pusher bar 435is located at the distance Y1 from the datum plane DP so as to providethe controller 333 with a known location of the push face PF atstartup/initialization of the bottom slip sheet remover 310.

The push face PF of the at least one pusher bar 435 may be located at awaiting position (see FIG. 9 ) at which the pusher bar 435 (e.g., themotors/actuators 430CD, 430L thereof) is positioned in anticipation forsignals from the controller 333 for removing a slip sheet 277. In thewaiting position the at least one pusher bar 435 is in the retractedposition and the push face PF of the at least one pusher bar is locateda predetermined distance Y2 from the datum plane DP. The predetermineddistance Y2 is a distance that provides clearance for robotic casemanipulator(s) 14 placement of pallet layers PL on the layer placeconveyor 320. As will be described herein, where a slip sheet 277 is notpresent/detected underneath the pallet layer PL the at least one pusherarm 435 remains at the waiting position and the conveyor portion 400 ofthe accumulator conveyor 325 conveys the pallet layer from the bottomslip sheet remover 310 to the spreader conveyor 330.

With the controller 333 commanding removal of a slip sheet 277, the pushface PF of the at least one pusher bar 435 is moved to a ready to lowerposition (FIG. 10 ) that is within the area DA (see also FIG. 7 ) of thesensor 476 field of view FOVP. To effect lowering of the at least onepusher bar 435 the push face PF of the at least one pusher bar 435 ismoved to a predetermined distance Y3 from the datum plane DP, where thedistance Y3 is within the bounds of the area DA. Here, with the slipsheet detected in the manner described herein, the pallet layer LP isconveyed in direction 499A to the end (prior to transition to thespreader conveyor 330) of the conveyor portion 400. The sensor 476 scansthe area DA and determines the presence of objects within the area DA.With substantially no objects in the area DA the pusher bar 435 moves toa ready to push position (FIG. 11 ). In the ready to push position thepush face PF remains within the area DA and the pusher bar 435 islowered to the deployed position as illustrated in FIG. 11 . Thecarriage 430C includes any suitable position/proximity sensors 1001,1002 that detect or otherwise effect determination of whether the pusherbar 435 is in the retracted position or the deployed position.

From the ready to push position the pusher bar 435 is moved, e.g., undercommand of controller 333 and by actuator 430L, in the conveyancedirection 499A to the push end position (FIG. 12 ) which is located adistance Y4 from the datum plane DP. With traverse of the pusher bar 435from the ready to push position (FIG. 11 ) to the push end position(FIG. 12 ) the push face PF of the at least one pusher bar 435 pushesthe cases CU of the pallet layer PL off of (i.e., strips the palletlayer PL off of) the slip sheet 277 and onto the spreader conveyor 330(see FIGS. 16A and 16B) (it is noted that with the cases CU being pushedby the push face, the slip sheet gripper 351 is positioned above theconveyor portion 400 of the accumulator conveyor 325). With the cases CUof the pallet layer PL transferred to the spreader conveyor 330 thepusher bar is pivoted to the retracted position so that the pusher bar435 is at a push end retracted position (FIG. 13 ). From the push endretracted position the pusher bar 435 is moved to the waiting position(FIG. 9 ) in anticipation of detection of another slip sheet 277 (notingthat with the pusher bar 435 moving to the waiting position, the slipsheet gripper 351 moves to grip the slip sheet 277 on the conveyorportion 400). Here, the retraction of the pusher 420 (e.g., effectingmovement of the pusher bar 435 to the waiting position) and slip sheet277 pick up for discharge with the slip sheet remover 350 are decoupledfrom each other (e.g., picking of the slip sheet may be effected withthe pusher bar 435 at the push end position, with the pusher bar 435 atthe waiting position, or with the pusher bar moving from the push endposition to the waiting position, where movement of the slip sheetremover 350 is independent from movement of the pusher 420) as will bedescribed further herein. The retraction of the pusher 420 and the slipsheet 277 pick up for discharge with the slip sheet remover 350 aresubstantially coincident, at least in part (e.g., retracting movement ofthe pusher 420 and the picking movement of the slip sheet remover 350may occur at the same time, at least for a portion of the respectivemovements). In one aspect, the pusher bar 435 closest to the slip sheetreceptacle 1666 may be retracted in direction 495 to a greater extentthan the pusher bar further from the slip sheet receptacle 1666 (seeFIG. 4A) to provide clearance for the slip sheet 277 being transferredto the slip sheet receptacle 1666.

It is noted that the time it takes for the at least one pusher arm 435to move from the waiting position and push the pallet layer PL may beless than a time it takes for the robotic case manipulator(s) 14 of thepalletizing cell 10 to transfer a pallet layer PL to the layer placeconveyor 320. The pushing of the pallet layer PL with the at least onepusher arm 435 occurs (e.g., the controller 333 coordinates the stoppingof the conveyor portion 400 and the movement of the at least one pusherarm 435) such that stoppage of the pallet layer PL in the conveyancedirection 499A on the bottom slip sheet remover 310 is minimized and theslip sheet removal system 300 provides a substantially steadystate/continuous conveyance of pallet layers/cases in the conveyancedirection 499A through the slip sheet removal system 300. For example,slip sheet 277 removal is decoupled from a state (e.g., on/conveying oroff/not conveying) of the layer place conveyor 320 and movement of thepusher 420. As described herein, a direction in which the slip sheetremover 350 moves (e.g., a travel path—see FIG. 16B for an exemplarytravel path although any suitable path may be followed) is such thatlayer place conveyor 320 feed of a next or subsequent pallet layer isunencumbered. Here, actuation of the slip sheet remover 350 may occursubstantially coincident with the at least one pusher arm 435 strippingof the pallet layer PL from the slip sheet 277, such that removal of theslip sheet 277 by the slip sheet remover is substantially proximate(e.g., in time) to a trailing side of the pallet layer PL (e.g. the sideof the pallet layer PL in substantial contact with the push face PF ofthe pusher bar 435) moving off of the slip sheet 277 (see FIG. 16B). Assuch, the slip sheet 277 is removed opportunistically with the layerplace conveyor 320 in the same state for stripping the pallet layer PLfrom the slip sheet 277 (i.e., removal of the slip sheet is decoupledfrom the layer place conveyor 320 state—the layer place conveyor stateremains unchanged for slip sheet removal). Here, substantiallysimultaneously with the slip sheet remover 350 lifting the slip sheet277 from the accumulator conveyor 325, the layer place conveyor 320 ischanged to the on state for conveyance of a next pallet layer. The nextpallet layer is fed onto the layer place conveyor 320 substantiallyproximate (e.g., in time) slip sheet 277 removal and the travelpath/direction of the slip sheet remover 350 is such that the feed ofthe next pallet layer along the layer place conveyor 320 isunencumbered. Here, the pallet layer PL being stripped from the slipsheet 277, the slip sheet 277 being opportunistically lifted from theaccumulator conveyor 325, and the next or subsequent pallet layer PLbeing placed on the layer place conveyor occur proximate (e.g., in time)to each other such that a substantially steady state/continuousconveyance of pallet layers/cases in the conveyance direction 499Athrough the slip sheet removal system 300 is effected.

Referring to FIGS. 1, 3, 4A, 4B, 5A, 5B, 5C, 15B, 16A, 16B, 17A, 17B,18A, 18B, and 19 an exemplary operation of the slip sheet removal system300 will be described in accordance with aspects of the disclosedembodiment. As described herein, the slip sheet removal system 300 isinitialized so that the position Y1 of the push face PF of the at leastone pusher bar 435 is known to the controller 333 (FIG. 8 ). The pusherbar 435 is moved, under command of the controller 333 and by actuator430L) to the waiting position (e.g., distance Y2—FIG. 9 ). The layerplace conveyor 320 is determined (e.g., by the presence sensor 477—seeFIG. 6 ) to be free of obstructions and the robotic case manipulator(s)14 of the palletizer cell 10 (e.g., that is communicably coupled to theslip sheet removal system 300) is operated to transfer a pallet layer PLto the layer place conveyor 320 so that the pallet layer PL is receivedby the slip sheet removal system 300 (FIG. 19 , Block 1900).

The pallet layer PL is conveyed in conveyance direction 499A along thelayer place conveyor 320 and the accumulator conveyor 325 past andthrough the field of view FOVS of the scanner 1405 (FIG. 15A) so thatthe pallet layer PL is scanned by the scanner 1405 (FIG. 19 , Block1905). With a slip sheet 277 present underneath the pallet layer PL, theslip sheet 277 blocks the field of view for the duration of transit ofthe pallet layer PL past and through the field of view FOVS. Asdescribed herein without a slip sheet 277 located underneath the palletlayer PL and with the differential conveying speeds between the layerplace conveyor 320 and the accumulator conveyor 325 the cases CU of thepallet layer are spaced apart by distance 1700 when they pass throughthe field of view FOVS of the scanner 1405 so that the cases CUintermittently block the field of view FOVS. The controller 333 isconfigured to detect the presence of a slip sheet 277 underneath thepallet layer PL based on whether the sensor signal from the scanner 1405indicates a substantially steady/constant sensor value or substantiallyperiodic or non-constant sensor value. The controller 333 may also beconfigured to detect the presence of a slip sheet 277 located on top ofthe pallet layer PL based on a magnitude of the substantially periodicor non-constant sensor value (e.g., the controller 333 is configured todiscriminate picking of a slip sheet 277 disposed on top of the palletlayer PL or a slip sheet 277 disposed underneath of the pallet layerPL).

FIGS. 18A-18C illustrate sensor signals obtained with the scanner 1405to effect, for exemplary purposes, a one-dimensional signal analysis forslip sheet 277 detection over time. Here, the scanner is for example theelectromagnetic beam sensor described above. An exemplary sensor signalindicating a presence of a slip sheet 277 underneath the pallet layer PLis illustrated in FIG. 18A. An exemplary sensor signal indicating anabsence of a slip sheet 277 is illustrated in FIG. 18B. An exemplarysensor signal indicating a presence of a slip sheet 277 on the top ofthe pallet layer PL is illustrated in FIG. 18C. FIG. 18A illustrates thesensor signal for the duration (e.g., time) of transit of the palletlayer PL past and through the field of view FOVS such that the slipsheet 277 blocks the field of view FOVS to produce a sensor signalhaving a substantially constant value. An exemplary sensor signalindicating an absence of a slip sheet 277 is illustrated in FIG. 18B.FIG. 18B also illustrates the sensor signal for the duration (e.g.,time) of transit of the pallet layer PL past and through the field ofview FOVS such that the cases CU intermittently block the field of viewFOVS to produce a sensor signal having a case detection value and a nullsignal between cases. It is noted that with the field of view unblockedbetween the cases, the sensor signal increases to the null or infinitevalue to provide the intermittent sensor signal indicating the absenceof a slip sheet 277. FIG. 18C illustrates the sensor signal for theduration (e.g., time) of transit of the pallet layer PL past and throughthe field of view FOVS such that the cases CU intermittently block thefield of view FOVS to produce a sensor signal having a case detectionvalue and a top slip sheet detected value between cases. Here, with thefield of view blocked by the slip sheet 277 located on the top of thepallet layer PL, the sensor signal increases to a value correspondingwith the top surface of the cases CU of the pallet layer PL to providethe intermittent sensor signal; however, as noted above the increase inmagnitude of the sensor signal between the cases CU is limited so as toindicate the presence of a slip sheet on the top of the pallet layer PL.The slip sheet 277 may be removed from the top of the pallet layer PL ina manner substantially similar to that described herein; however, the atleast one pusher arm need not push the pallet layer from the slip sheet,rather the slip sheet remover 350 may pick the slip sheet 277substantially directly from the top of the pallet layer PL.

FIGS. 18D-18F illustrate sensor signals obtained with the scanner 1405to effect, for exemplary purposes, at least a two-dimensional (e.g.,depth map) signal analysis for slip sheet 277 detection over time. Here,the scanner is for example the imaging sensor (also referred to as aheight sensor) described above. An exemplary depth map indicating apresence of a slip sheet 277 underneath the pallet layer PL of caseunits CU is illustrated in FIG. 18D. An exemplary depth map indicatingan absence of a slip sheet 277 is illustrated in FIG. 18C. An exemplarydepth map indicating a presence of a slip sheet 277 on the top of thecase units CU of the pallet layer PL is illustrated in FIG. 18D. Asdescribed above, the slip sheet detection sensor 1400 includes thescanner 1405 (also referred to as a height sensor). Here, the slip sheetdetection sensor also includes an encoder 1599 (also referred to as adistance sensor—see FIG. 15B). The scanner 1405 configured to measure aheight between a surface of the seated destacked layer PL and apredetermined datum (such as the conveyance surface 401) and send heightmeasure data embodying the height measure to the controller 333, and theencoder 1599 is configured to measure a distance (e.g., such as aconveyor tick distance) in which the scanner 1405 registers the heightmeasure and send the controller 333 distance measure data embodying thedistance measure. The controller 333 is configured to merge the heightmeasure data and distance measure data forming a two-dimensional depthmap characterizing the surface of the destacked layer PL seated on theaccumulator conveyor 325, and the controller 333 determines presence ofthe slip sheet 277 and position contacting the at least one of theuppermost surface PLUS and bottom surface PLLS of the seated destackedlayer PL. For example, as described above, the field of view FOVS of thescanner 1405 is substantially planar and can be considered as a singlescan line with respect to a measured movement of the case units CU alongthe accumulator conveyor 325. Here, the value of each data point in thescan line is a distance between a surface (e.g., of the slip sheet 277or of a case unit CU) and the scanner 1405. The accumulator conveyor 325includes the encoder 1599 (also referred to herein as a distance sensorand with the scanner 1450 forms the slip sheet detection sensor 1400—seeFIG. 15B) so that each scan line obtained by the scanner 1405 over themeasured movement has a reference position indicating its displacementalong the movement direction 499 of the accumulator conveyor 325. Theencoder 1599 and scanner 1405 may be calibrated with respect to theaccumulator conveyor 325 so that the accumulator conveyor's tick size(with respect to the number of ticks the encoder generates when theconveyor moves one meter or any other suitable distance measure) isknown, the scale in the direction perpendicular to the conveyancesurface 401 of the accumulator conveyor 325 is known, and a referenceline representing the conveyance surface 401 is known, where thesecalibrated parameters are accessible by or stored in the controller 333.With the encoder 1599 and scanner 1405 calibrated, and knowing thedisplacement between scan lines and the distance between the scanner andthe surfaces, the controller 333, via any suitable image processingalgorithms, converts the scan lines from the scanner 1405 (e.g., withthe case units CU moving in the conveyance traverse direction 499) intoa two-dimensional depth map such that every pixel is of a known size inmillimeters (or any other suitable unit of measure) effecting accuratemeasurements of the case units CU and slip sheets 277 conveyed on theaccumulator conveyor 325. Here, every pixel's value in the depth map isthe distance, perpendicular to the conveyance surface 401, between thedetected object (e.g., slip sheet 277 or case unit CU) and theconveyance surface 401.

FIG. 18D illustrates the two dimensional depth map for a measuredmovement (e.g., distance) of transit of the pallet layer PL past andthrough the field of view FOVS such that the slip sheet 277 blocks thefield of view FOVS to produce a two-dimensional depth map having asubstantially constant value. An exemplary two-dimensional depth mapindicating an absence of a slip sheet 277 is illustrated in FIG. 18Ewhere the case units CU are illustrated and the spaces between the caseunits CU is substantially a null value. In FIG. 18E the two-dimensionaldepth map is illustrated for the measured movement of transit of thepallet layer PL past and through the field of view FOVS such that thecases CU intermittently block the field of view FOVS to produce thetwo-dimensional depth map having a case detection value and a nullsignal between cases. It is noted that with the field of view unblockedbetween the cases, the two-dimensional depth map pixel distance dataincreases to the null or infinite value indicating the absence of a slipsheet 277. FIG. 18F illustrates the two-dimensional depth map for themeasured movement of transit of the pallet layer PL past and through thefield of view FOVS such that the cases CU intermittently block the fieldof view FOVS to produce a two-dimensional depth map having a casedetection value and a top slip sheet detected value between cases. Here,with the field of view blocked by the slip sheet 277 located on the topof the pallet layer PL, the distance value of the pixels between thecases CU increases to a value corresponding with the top surface of thecases CU of the pallet layer PL; however, as noted above the distancevalue of the pixels, in the two-dimensional depth map, between the casesCU is limited so as to indicate the presence of a slip sheet 277 on thetop of the pallet layer PL. The slip sheet 277 may be removed from thetop of the pallet layer PL in a manner substantially similar to thatdescribed herein; however, the at least one pusher arm need not push thepallet layer from the slip sheet, rather the slip sheet remover 350 maypick the slip sheet 277 substantially directly from the top of thepallet layer PL.

The controller 333 is configured to identify/detect a presence of a(bottom) slip sheet 277 based on the substantially constant sensor value(see FIG. 18A) during transit of the pallet layer PL past the andthrough the field of view FOVS. The controller 333 is also configured toidentify/detect an absence of a slip sheet 277 and/or a presence of a(top) slip sheet 277 based on the intermittent sensor value (see FIGS.18B and 18C) during transit of the pallet layer PL past the and throughthe field of view FOVS.

In other aspects, another scanner (similar to scanner 1405 may beprovided above the conveyor portion 400 so as to determine a presence ofa top slip sheet 277 while the scanner 1405 determines the presence ofthe bottom slip sheet. Here, if both a top and bottom slip sheet 277 arepresent the slip sheet remover 350 may remove the top slip sheet in themanner noted above, the at least one pusher arm may push the palletlayer off the bottom slip sheet 277, and the slip sheet remover 350 maythen remove the bottom slip sheet 277 in the manner described herein.

With the absence of the slip sheet 277, conveyance of the cases CU ofthe pallet layer PL in the conveyance direction 499A is uninterruptedand the cases are conveyed by the slip sheet removal system 300 withoutstoppage/interruption (FIG. 19 , Block 1930). With the presence of aslip sheet 277 the pallet layer PL is conveyed in direction 499A to theend of the conveyor portion 400 (as described herein) of the bottom slipsheet remover 310 and the conveyor portion 400 movement is arrested(e.g., stopped) (FIG. 19 , Block 1915). The lock 401L is actuated tohold the conveyance surface 401 of the conveyor portion 400substantially stationary relative to the conveyance direction 499. Asdescribed above, the conveyance surface 401 has a substantially uniform(e.g., common or steady state) coefficient of friction. Thesubstantially uniform (e.g., common or steady state) coefficient offriction of the conveyance surface 401 (e.g., such as of thecontinuous/solid rubber top (endless) belt 401R, the perforated rubbertop (endless) belt 401P, and the more than one rubber top (endless) belt401C—see FIGS. 5A-5C) is configured to both provide sufficient frictionto convey the pallet layer in the conveyance direction 499 and to gripthe slip sheet 277 and hold the slip sheet substantially stationaryrelative to the conveyance direction with the movement of the conveyorsurface 401 held substantially stationary by the lock 401L.

In some aspects (see FIGS. 5B and 5C) suction gripping of the slip sheet277 may also be provided in addition to the substantially uniform (e.g.,common or steady state) coefficient of friction. For example, in theaspect illustrated in FIG. 5B the bottom slip sheet remover 310 mayinclude any suitable vacuum source 555 in communication with theperforations of the perforated rubber top (endless) belt 401P. Thevacuum source 555 is actuated, with the pallet layer disposed at the endof the conveyor portion 400 and with the movement of the conveyancesurface 401 in the conveyance direction 499A arrested, so that thevacuum source 555 provides suction through the perorations that hold theslip sheet 277 stationary on the conveyance surface 401. In the aspectillustrated in FIG. 5C, the bottom slip sheet remover 310 may includethe vacuum source 555 and deployable suction cups 577. The deployablesuction cups are disposed below a plane defined by the conveyancesurface 401 with conveyance of the pallet layer PL by the conveyorportion 400. With the movement of the conveyance surface 401 arrestedand the pallet layer PL disposed at the end of the conveyor portion 400(as described herein) the suction cups 577 are raised in/along the Zdirection/axis to or above the plane defined by the conveyance surface401 so that the suction cups 577 grip the slip sheet 277 held on theconveyance surface 401.

As described herein, the push face PF of the at least one pusher bar 435is moved from the waiting position (e.g., distance Y2—FIG. 9 ) to theready to lower position (e.g., distance Y3—FIG. 10 ). The presencesensor 476 (FIG. 7 ) determines (with the controller 333) that the areaDA is free from obstructions and the at least one pusher arm 435 ispivoted to the deployed position to place the at least one pusher arm435 in the ready to push position (FIG. 11 ). The at least one pusherbar 435 is moved in the conveyance direction 499A so as to contact thepallet layer PL and push the pallet layer in the conveyance direction499A with the slip sheet 277 being held substantially stationaryrelative to the conveyance direction 499A by at least the conveyancesurface 401 so as to strip the pallet layer PL off of the slip sheet277. The at least one pusher bar 435 pushes the pallet layer PL from theconveyor portion 400 (FIG. 19 , Block 1920) and substantially onto thespreader conveyor 330 (for conveyance from the slip sheet removal system300) so that the cases CU of the pallet layer are pushed off of the slipsheet 277 and the slip sheet 277 is fully exposed.

The controller 333 commands the slip sheet remover 350 to move the slipsheet gripper 351 to the slip sheet. The slip sheet gripper 351 gripsthe slip sheet 277 and removes the slip sheet 277 from the conveyorportion 400 (FIG. 19 , Block 1925). The slip sheet remover 350 moves theslip sheet gripper 351 and the slip sheet 277 held thereby to the slipsheet receptacle 1666. The slip sheet gripper 351 releases the slipsheet 277 for placement of the slip sheet into the slip sheet receptacle1666. With the slip sheet 277 removed the at least one pusher arm 435 ismoved to the waiting position and the lock 401L for conveyor portion 400is released. The conveyor portion 400 is actuated to convey a nextpallet layer received by the slip sheet removal system 300 in theconveyance direction 499A and the slip sheet removal system 300 (e.g.,controller 333) sends a signal to the palletizer cell 10 for placementof the next/another pallet layer PL.

Referring to FIGS. 3, 4A, and 4B the movement of the at least one pusherbar 435 is monitored by the controller 333 to determine whether the atleast one pusher bar 435 is pushing the pallet layer over the surface ofa slip sheet 277 or over the conveyance surface 401 of the bottom slipsheet remover 310. The controller 333 is configured to monitor themovement of the at least one pusher bar by determining a force appliedby the respective actuator 430L of the at least one pusher arm 435. Forexample, based on a weight of the pallet layer PL (as determined by thepalletizer cell 10 or informed by the controller 199C according to apallet load plan) and packaging type, the amount of torque/force theactuator 430L should apply (i.e., a predetermined/expected force) tomove the pallet layer over the surface of the slip sheet 277 isdetermined by the controller 333. If the amount of torque/force appliedby the actuator 430L exceeds the predetermined force by a predeterminedamount (e.g., tolerance) the at least one pusher arm 435 may be pushingthe pallet load over the conveyance surface 401 (rather than over thesurface of the slip sheet) and/or the case(s) of the pallet layer may bestuck to the slip sheet where the at least one pusher arm 435 is pushingboth the pallet layer PL and the slip sheet 277 over the conveyancesurface 401. Here the controller 333 includes a table that informs ofthe friction coefficient for each type of packaging (e.g., regularcorrugated cardboard, shrink wrap, shiny printed cardboard, etc.)handled by the slip sheet removal system 300. With the frictioncoefficient of the different types of packaging known the controller 333is configured to determine the predetermined torque/force using, forexample, the following equation:

${{EF}({Nm})} = \frac{{{LW}\left( {kg} \right)} \times {G\left( \frac{m}{s^{2}} \right)} \times {Fc} \times 0.045845(m)}{50}$

where units are provided in brackets and EF is thepredetermined/expected force in Nm, LW is the pallet layer weight in Kg,G is the acceleration due to gravity (e.g., 9.81 m/s²) and Fc is thefriction coefficient of the packaging. Where the controller 333determines an actual force of the actuator 430L exceeds thepredetermined force by the predetermined amount (tolerance) thecontroller 333 effects notification (e.g., aural, visual, etc.) to anoperator and stops motion of the actuator 430L. The operator may,through a user interface 333U of the controller 333, effect manualretraction of the at least one pusher bar 435 and conveyance of thepallet layer PL (with or without slip sheet presence) by the conveyorportion 400 through and past the slip sheet removal system 300. Theoperator may also, through the user interface 333U, command continuedoperation of the at least one pusher bar 435, such as where the actualforce exerted by the actuator 430L is within actuator operationallimits, so that the at least one pusher bar 435 pushes the pallet layerto the spreader conveyor 330.

Referring to FIGS. 1, 3, 4A, 4B, 5A, 5B, 5C, 15B, 16A, 16B, 17A, 17B,18A, 18B, and 20 , a method for destacking a pallet layer PL, from astacked layer pallet load PAL, with the layer destacking system LDSdescribed herein will be described. The method includes seating thedestacked pallet layer PL on a layer place conveyor 320 (FIG. 20 , Block2000). As described herein, the layer place conveyor 320 has a conveyingsurface 321CS with a conveyance traverse direction 499 that traverses(e.g., moves) the seated pallet layer PL off the layer place conveyor320. The slip sheet detection sensor (such as slip sheet detector 1400)that is coupled to the layer place conveyor 320 senses a slip sheet 277(FIG. 20 , Block 2010) in contact with the seated destacked pallet layerPL on at least one of the uppermost surface PLUS and the bottom surfacePLLS of the seated destacked pallet layer PL, in the manner describedherein. The controller 333 receives a signal from the slip sheetdetection sensor identifying presence of the slip sheet 277 (FIG. 20 ,Block 2020). The controller 333 determines from the received signal theslip sheet 277 contacting the at least one of the uppermost surface PLUSand the bottom surface PLLS of the seated destacked pallet layer PL. Theslip sheet remover 310 engages, above the layer place conveyor 320 andwith the slip sheet remover 310 extending at least in part over thelayer place conveyor, the slip sheet 277 contacting the at least one ofthe uppermost surface PLUS and the bottom surface PLLS of the seateddestacked pallet layer PL to remove the slip sheet 277 from theaccumulator conveyor 325 (FIG. 20 , Block 2030) in the manner describedherein. Here, as described herein, the controller 333 is operablyconnected to the slip sheet remover 310 so as to actuate the slip sheetremover 310 engaging the slip sheet 277 contacting the at least one ofthe uppermost surface PLUS and the bottom surface PLLS, and lifting theslip sheet 277 effecting discharge of the slip sheet 277 off theaccumulator conveyor 325.

In accordance with one or more aspects of the disclosed embodiment alayer destacking system for destacking a layer from a stacked layerpallet load, the layer destacking system includes a layer seatingplatform configured so as to seat the destacked layer on the layerseating platform, and having a conveying surface with a conveyancetraverse direction that traverses the seated destacked layer off thelayer seating platform; a slip sheet detection sensor coupled to thelayer seating platform and arranged to sense a slip sheet in contactwith the seated destacked layer on at least one of an uppermost surfaceand a bottom surface of the seated destacked layer; a slip sheet pickupremoval mechanism extending at least in part over the layer seatingplatform and configured so as to engage, above the layer seatingplatform, the slip sheet contacting the at least one of the uppermostsurface and the bottom surface of the seated destacked layer; and acontroller communicably coupled to the slip sheet detection sensor so asto receive a signal from the slip sheet detection sensor identifyingpresence of the slip sheet, the controller is configured to determinefrom the received signal the slip sheet contacting the at least one ofthe uppermost surface and the bottom surface of the seated destackedlayer; wherein the controller is operably connected to the slip sheetpickup removal mechanism so as to actuate the slip sheet pickup removalmechanism engaging the slip sheet contacting the at least one of theuppermost surface and the bottom surface, and lifting the slip sheeteffecting discharge of the slip sheet off the layer seating platform.

In accordance with one or more aspects of the disclosed embodiment theslip sheet pickup removal mechanism is a gantry above the layer seatingplatform.

In accordance with one or more aspects of the disclosed embodiment theslip sheet pickup removal mechanism has a pick head that engages anupper surface of the slip sheet.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is disposed to sense the slip sheet on theat least one of the uppermost surface and the bottom surface of theseated destacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is disposed to sense the slip sheet on theat least one of the uppermost surface and the bottom surface of theseated destacked layer with the destacked layer seated on the conveyingsurface.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is an electromagnetic beam sensor arrangedso as to emit a sensing beam in a direction that crosses a seating planeof the conveying surface so as to sense the slip sheet on the at leastone of the uppermost surface and the bottom surface of the seateddestacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is an imaging sensor registering the slipsheet on the at least one of the uppermost surface and the bottomsurface of the seated destacked layer in a direction crossing a seatingplane of the seated destacked layer seated on the conveying surface.

In accordance with one or more aspects of the disclosed embodiment thelayer destacking system further includes a displacer movably coupled tothe layer seating platform and actuable in a direction aligned with theconveyance traverse direction between an advanced position and aretracted position that displaces the seated destacked layer and theslip sheet on the bottom surface relative to each other stripping theseated destacked layer and slip sheet from each other.

In accordance with one or more aspects of the disclosed embodiment thedisplacer is actuable to raise and lower to and from engaged anddisengaged positions.

In accordance with one or more aspects of the disclosed embodimentretraction of the displacer and slip sheet pick up for discharge withthe slip sheet pickup removal mechanism are decoupled from each other.

In accordance with one or more aspects of the disclosed embodimentretraction of the displacer and slip sheet pick up for discharge withthe slip sheet pickup removal mechanism are substantially coincident, atleast in part.

In accordance with one or more aspects of the disclosed embodiment alayer destacking system for destacking a layer from a stacked layerpallet load, the layer destacking system includes a layer seatingplatform configured so as to seat the destacked layer on the layerseating platform, and having a conveying surface with a conveyancetraverse direction that traverses the seated destacked layer off thelayer seating platform; a slip sheet detection sensor coupled to thelayer seating platform and arranged to sense a slip sheet in contactwith the seated destacked layer on at least one of an uppermost surfaceand a bottom surface of the seated destacked layer; a slip sheet pickupremoval mechanism extending at least in part over the layer seatingplatform and configured so as to engage, above the layer seatingplatform, the slip sheet contacting the at least one of the uppermostsurface and the bottom surface of the seated destacked layer; and acontroller communicably coupled to the slip sheet detection sensor so asto receive a signal from the slip sheet detection sensor identifyingpresence of the slip sheet; wherein the controller is operably connectedto the slip sheet pickup removal mechanism so as to actuate the slipsheet pickup removal mechanism engaging the slip sheet contacting the atleast one of the uppermost surface and the bottom surface, and liftingthe slip sheet effecting discharge of the slip sheet off the layerseating platform based on the signal.

In accordance with one or more aspects of the disclosed embodiment thecontroller is configured to determine, from the signal, the slip sheetcontacting the at least one of the uppermost surface and the bottomsurface of the seated destacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet pickup removal mechanism is a gantry above the layer seatingplatform.

In accordance with one or more aspects of the disclosed embodiment theslip sheet pickup removal mechanism has a pick head that engages anupper surface of the slip sheet.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is disposed to sense the slip sheet on theat least one of the uppermost surface and the bottom surface of theseated destacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is disposed to sense the slip sheet on theat least one of the uppermost surface and the bottom surface of theseated destacked layer with the destacked layer seated on the conveyingsurface.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is an electromagnetic beam sensor arrangedso as to emit a sensing beam in a direction that crosses a seating planeof the conveying surface so as to sense the slip sheet on the at leastone of the uppermost surface and the bottom surface of the seateddestacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is an imaging sensor registering the slipsheet on the at least one of the uppermost surface and the bottomsurface of the seated destacked layer in a direction crossing a seatingplane of the seated destacked layer seated on the conveying surface.

In accordance with one or more aspects of the disclosed embodiment thelayer destacking system further includes a displacer movably coupled tothe layer seating platform and actuable in a direction aligned with theconveyance traverse direction between an advanced position and aretracted position that displaces the seated destacked layer and theslip sheet on the bottom surface relative to each other stripping theseated destacked layer and slip sheet from each other.

In accordance with one or more aspects of the disclosed embodiment thedisplacer is actuable to raise and lower to and from engaged anddisengaged positions.

In accordance with one or more aspects of the disclosed embodimentretraction of the displacer and slip sheet pick up for discharge withthe slip sheet pickup removal mechanism are decoupled from each other.

In accordance with one or more aspects of the disclosed embodimentretraction of the displacer and slip sheet pick up for discharge withthe slip sheet pickup removal mechanism are substantially coincident, atleast in part.

In accordance with one or more aspects of the disclosed embodiment amethod for destacking a layer, from a stacked layer pallet load, with alayer destacking system, is provided. The method includes seating thedestacked layer on a layer seating platform, where the layer seatingplatform has a conveying surface with a conveyance traverse directionthat traverses the seated destacked layer off the layer seatingplatform; sensing, with a slip sheet detection sensor coupled to thelayer seating platform, a slip sheet in contact with the seateddestacked layer on at least one of an uppermost surface and a bottomsurface of the seated destacked layer; engaging, above the layer seatingplatform and with a slip sheet pickup removal mechanism extending atleast in part over the layer seating platform, the slip sheet contactingthe at least one of the uppermost surface and the bottom surface of theseated destacked layer; and receiving, with a controller communicablycoupled to the slip sheet detection sensor, a signal from the slip sheetdetection sensor identifying presence of the slip sheet, where thecontroller determines from the received signal the slip sheet contactingthe at least one of the uppermost surface and the bottom surface of theseated destacked layer; wherein the controller is operably connected tothe slip sheet pickup removal mechanism so as to actuate the slip sheetpickup removal mechanism engaging the slip sheet contacting the at leastone of the uppermost surface and the bottom surface, and lifting theslip sheet effecting discharge of the slip sheet off the layer seatingplatform.

In accordance with one or more aspects of the disclosed embodiment theslip sheet pickup removal mechanism is a gantry above the layer seatingplatform.

In accordance with one or more aspects of the disclosed embodiment theslip sheet pickup removal mechanism has a pick head that engages anupper surface of the slip sheet.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is disposed to sense the slip sheet on theat least one of the uppermost surface and the bottom surface of theseated destacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is disposed to sense the slip sheet on theat least one of the uppermost surface and the bottom surface of theseated destacked layer with the destacked layer seated on the conveyingsurface.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is an electromagnetic beam sensor arrangedso as to emit a sensing beam in a direction that crosses a seating planeof the conveying surface so as to sense the slip sheet on the at leastone of the uppermost surface and the bottom surface of the seateddestacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is an imaging sensor registering the slipsheet on the at least one of the uppermost surface and the bottomsurface of the seated destacked layer in a direction crossing a seatingplane of the seated destacked layer seated on the conveying surface.

In accordance with one or more aspects of the disclosed embodiment themethod further includes actuating a displacer, that is movably coupledto the layer seating platform, in a direction aligned with theconveyance traverse direction between an advanced position and aretracted position that displaces the seated destacked layer and theslip sheet on the bottom surface relative to each other stripping theseated destacked layer and slip sheet from each other.

In accordance with one or more aspects of the disclosed embodiment thedisplacer is actuable to raise and lower to and from engaged anddisengaged positions.

In accordance with one or more aspects of the disclosed embodimentretraction of the displacer and slip sheet pick up for discharge withthe slip sheet pickup removal mechanism are decoupled from each other.

In accordance with one or more aspects of the disclosed embodimentretraction of the displacer and slip sheet pick up for discharge withthe slip sheet pickup removal mechanism are substantially coincident, atleast in part.

In accordance with one or more aspects of the disclosed embodiment amethod for destacking a layer, from a stacked layer pallet load, with alayer destacking system, is provided. The method includes seating thedestacked layer on a layer seating platform, where the layer seatingplatform has a conveying surface with a conveyance traverse directionthat traverses the seated destacked layer off the layer seatingplatform; sensing, with a slip sheet detection sensor coupled to thelayer seating platform, a slip sheet in contact with the seateddestacked layer on at least one of an uppermost surface and a bottomsurface of the seated destacked layer; engaging, above the layer seatingplatform and with a slip sheet pickup removal mechanism extending atleast in part over the layer seating platform, the slip sheet contactingthe at least one of the uppermost surface and the bottom surface of theseated destacked layer; and receiving, with a controller communicablycoupled to the slip sheet detection sensor, a signal from the slip sheetdetection sensor identifying presence of the slip sheet; wherein thecontroller is operably connected to the slip sheet pickup removalmechanism so as to actuate the slip sheet pickup removal mechanismengaging the slip sheet contacting the at least one of the uppermostsurface and the bottom surface, and lifting the slip sheet effectingdischarge of the slip sheet off the layer seating platform based on thesignal.

In accordance with one or more aspects of the disclosed embodiment thecontroller is configured to determine, from the signal, the slip sheetcontacting the at least one of the uppermost surface and the bottomsurface of the seated destacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet pickup removal mechanism is a gantry above the layer seatingplatform.

In accordance with one or more aspects of the disclosed embodiment theslip sheet pickup removal mechanism has a pick head that engages anupper surface of the slip sheet.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is disposed to sense the slip sheet on theat least one of the uppermost surface and the bottom surface of theseated destacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is disposed to sense the slip sheet on theat least one of the uppermost surface and the bottom surface of theseated destacked layer with the destacked layer seated on the conveyingsurface.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is an electromagnetic beam sensor arrangedso as to emit a sensing beam in a direction that crosses a seating planeof the conveying surface so as to sense the slip sheet on the at leastone of the uppermost surface and the bottom surface of the seateddestacked layer.

In accordance with one or more aspects of the disclosed embodiment theslip sheet detection sensor is an imaging sensor registering the slipsheet on the at least one of the uppermost surface and the bottomsurface of the seated destacked layer in a direction crossing a seatingplane of the seated destacked layer seated on the conveying surface.

In accordance with one or more aspects of the disclosed embodiment themethod further includes actuating a displacer, that is movably coupledto the layer seating platform, in a direction aligned with theconveyance traverse direction between an advanced position and aretracted position that displaces the seated destacked layer and theslip sheet on the bottom surface relative to each other stripping theseated destacked layer and slip sheet from each other.

In accordance with one or more aspects of the disclosed embodiment thedisplacer is actuable to raise and lower to and from engaged anddisengaged positions.

In accordance with one or more aspects of the disclosed embodimentretraction of the displacer and slip sheet pick up for discharge withthe slip sheet pickup removal mechanism are decoupled from each other.

In accordance with one or more aspects of the disclosed embodimentretraction of the displacer and slip sheet pick up for discharge withthe slip sheet pickup removal mechanism are substantially coincident, atleast in part.

In accordance with one or more aspects of the disclosed embodiment alayer destacking system for destacking a layer from a stacked layerpallet load is provided. The layer destacking system includes: a layerseating platform configured so as to seat the destacked layer on thelayer seating platform, and having a conveying surface with a conveyancetraverse direction that traverses the seated destacked layer off thelayer seating platform; a slip sheet detection sensor coupled to thelayer seating platform and arranged to sense a slip sheet in contactwith the seated destacked layer on at least one of an uppermost surfaceand a bottom surface of the seated destacked layer; a slip sheet pickupremoval mechanism extending at least in part over the layer seatingplatform and configured so as to engage, above the layer seatingplatform, the slip sheet contacting the at least one of the uppermostsurface and the bottom surface of the seated destacked layer; and acontroller communicably coupled to the slip sheet detection sensor;wherein the slip sheet detection sensor includes a height sensorconfigured to measure a height between a surface of the seated destackedlayer and a predetermined datum and send height measure data embodyingthe height measure to the controller, and the slip sheet detectionsensor includes a distance sensor configured to measure a distance inwhich the height sensor registers the height measure and send thecontroller distance measure data embodying the distance measure; andwherein the controller is configured to merge the height measure dataand distance measure data forming a 2D depth map characterizing thesurface, and the controller determines presence of the slip sheet andposition contacting the at least one of the uppermost surface and bottomsurface of the seated destacked layer.

In accordance with one or more aspects of the disclosed embodiment, thedistance sensor is configured to measure the distance in the conveyancetraverse direction.

It should be understood that the foregoing description is onlyillustrative of the aspects of the disclosed embodiment. Variousalternatives and modifications can be devised by those skilled in theart without departing from the aspects of the disclosed embodiment.Accordingly, the aspects of the disclosed embodiment are intended toembrace all such alternatives, modifications and variances that fallwithin the scope of any claims appended hereto. Further, the mere factthat different features are recited in mutually different dependent orindependent claims does not indicate that a combination of thesefeatures cannot be advantageously used, such a combination remainingwithin the scope of the aspects of the disclosed embodiment.

What is claimed is:
 1. A layer destacking system for destacking a layerfrom a stacked layer pallet load, the layer destacking systemcomprising: a layer seating platform configured so as to seat thedestacked layer on the layer seating platform, and having a conveyingsurface with a conveyance traverse direction that traverses the seateddestacked layer off the layer seating platform; a slip sheet detectionsensor coupled to the layer seating platform and arranged to sense aslip sheet in contact with the seated destacked layer on at least one ofan uppermost surface and a bottom surface of the seated destacked layer;a slip sheet pickup removal mechanism extending at least in part overthe layer seating platform and configured so as to engage, above thelayer seating platform, the slip sheet contacting the at least one ofthe uppermost surface and the bottom surface of the seated destackedlayer; and a controller communicably coupled to the slip sheet detectionsensor so as to receive a signal from the slip sheet detection sensoridentifying presence of the slip sheet, the controller is configured todetermine from the received signal the slip sheet contacting the atleast one of the uppermost surface and the bottom surface of the seateddestacked layer; wherein the controller is operably connected to theslip sheet pickup removal mechanism so as to actuate the slip sheetpickup removal mechanism engaging the slip sheet contacting the at leastone of the uppermost surface and the bottom surface, and lifting theslip sheet effecting discharge of the slip sheet off the layer seatingplatform.
 2. The layer destacking system of claim 1, wherein the slipsheet pickup removal mechanism is a gantry above the layer seatingplatform.
 3. The layer destacking system of claim 1, wherein the slipsheet pickup removal mechanism has a pick head that engages an uppersurface of the slip sheet.
 4. The layer destacking system of claim 1,wherein the slip sheet detection sensor is disposed to sense the slipsheet on the at least one of the uppermost surface and the bottomsurface of the seated destacked layer.
 5. The layer destacking system ofclaim 1, wherein the slip sheet detection sensor is an electromagneticbeam sensor arranged so as to emit a sensing beam in a direction thatcrosses a seating plane of the conveying surface so as to sense the slipsheet on the at least one of the uppermost surface and the bottomsurface of the seated destacked layer.
 6. The layer destacking system ofclaim 1, wherein the slip sheet detection sensor is an imaging sensorregistering the slip sheet on the at least one of the uppermost surfaceand the bottom surface of the seated destacked layer in a directioncrossing a seating plane of the seated destacked layer seated on theconveying surface.
 7. The layer destacking system of claim 1, furthercomprising a displacer movably coupled to the layer seating platform andactuable in a direction aligned with the conveyance traverse directionbetween an advanced position and a retracted position that displaces theseated destacked layer and the slip sheet on the bottom surface relativeto each other stripping the seated destacked layer and slip sheet fromeach other.
 8. A layer destacking system for destacking a layer from astacked layer pallet load, the layer destacking system comprising: alayer seating platform configured so as to seat the destacked layer onthe layer seating platform, and having a conveying surface with aconveyance traverse direction that traverses the seated destacked layeroff the layer seating platform; a slip sheet detection sensor coupled tothe layer seating platform and arranged to sense a slip sheet in contactwith the seated destacked layer on at least one of an uppermost surfaceand a bottom surface of the seated destacked layer; a slip sheet pickupremoval mechanism extending at least in part over the layer seatingplatform and configured so as to engage, above the layer seatingplatform, the slip sheet contacting the at least one of the uppermostsurface and the bottom surface of the seated destacked layer; and acontroller communicably coupled to the slip sheet detection sensor so asto receive a signal from the slip sheet detection sensor identifyingpresence of the slip sheet; wherein the controller is operably connectedto the slip sheet pickup removal mechanism so as to actuate the slipsheet pickup removal mechanism engaging the slip sheet contacting the atleast one of the uppermost surface and the bottom surface, and liftingthe slip sheet effecting discharge of the slip sheet off the layerseating platform based on the signal.
 9. The layer destacking system ofclaim 8, wherein the controller is configured to determine, from thesignal, the slip sheet contacting the at least one of the uppermostsurface and the bottom surface of the seated destacked layer.
 10. Thelayer destacking system of claim 8, wherein the slip sheet pickupremoval mechanism has a pick head that engages an upper surface of theslip sheet.
 11. The layer destacking system of claim 8, wherein the slipsheet detection sensor is disposed to sense the slip sheet on the atleast one of the uppermost surface and the bottom surface of the seateddestacked layer.
 12. The layer destacking system of claim 8, wherein theslip sheet detection sensor is an electromagnetic beam sensor arrangedso as to emit a sensing beam in a direction that crosses a seating planeof the conveying surface so as to sense the slip sheet on the at leastone of the uppermost surface and the bottom surface of the seateddestacked layer.
 13. The layer destacking system of claim 8, wherein theslip sheet detection sensor is an imaging sensor registering the slipsheet on the at least one of the uppermost surface and the bottomsurface of the seated destacked layer in a direction crossing a seatingplane of the seated destacked layer seated on the conveying surface. 14.The layer destacking system of claim 8, further comprising a displacermovably coupled to the layer seating platform and actuable in adirection aligned with the conveyance traverse direction between anadvanced position and a retracted position that displaces the seateddestacked layer and the slip sheet on the bottom surface relative toeach other stripping the seated destacked layer and slip sheet from eachother.
 15. A method for destacking a layer, from a stacked layer palletload, with a layer destacking system, the method comprising: seating thedestacked layer on a layer seating platform, where the layer seatingplatform has a conveying surface with a conveyance traverse directionthat traverses the seated destacked layer off the layer seatingplatform; sensing, with a slip sheet detection sensor coupled to thelayer seating platform, a slip sheet in contact with the seateddestacked layer on at least one of an uppermost surface and a bottomsurface of the seated destacked layer; engaging, above the layer seatingplatform and with a slip sheet pickup removal mechanism extending atleast in part over the layer seating platform, the slip sheet contactingthe at least one of the uppermost surface and the bottom surface of theseated destacked layer; and receiving, with a controller communicablycoupled to the slip sheet detection sensor, a signal from the slip sheetdetection sensor identifying presence of the slip sheet, where thecontroller determines from the received signal the slip sheet contactingthe at least one of the uppermost surface and the bottom surface of theseated destacked layer; wherein the controller is operably connected tothe slip sheet pickup removal mechanism so as to actuate the slip sheetpickup removal mechanism engaging the slip sheet contacting the at leastone of the uppermost surface and the bottom surface, and lifting theslip sheet effecting discharge of the slip sheet off the layer seatingplatform.
 16. The method of claim 15, wherein the slip sheet pickupremoval mechanism is a gantry above the layer seating platform.
 17. Themethod of claim 15, wherein the slip sheet pickup removal mechanism hasa pick head that engages an upper surface of the slip sheet.
 18. Themethod of claim 15, wherein the slip sheet detection sensor is disposedto sense the slip sheet on the at least one of the uppermost surface andthe bottom surface of the seated destacked layer.
 19. The method ofclaim 15, wherein the slip sheet detection sensor is an electromagneticbeam sensor arranged so as to emit a sensing beam in a direction thatcrosses a seating plane of the conveying surface so as to sense the slipsheet on the at least one of the uppermost surface and the bottomsurface of the seated destacked layer.
 20. The method of claim 15,wherein the slip sheet detection sensor is an imaging sensor registeringthe slip sheet on the at least one of the uppermost surface and thebottom surface of the seated destacked layer in a direction crossing aseating plane of the seated destacked layer seated on the conveyingsurface.
 21. The method of claim 15, further comprising actuating adisplacer, that is movably coupled to the layer seating platform, in adirection aligned with the conveyance traverse direction between anadvanced position and a retracted position that displaces the seateddestacked layer and the slip sheet on the bottom surface relative toeach other stripping the seated destacked layer and slip sheet from eachother.
 22. A method for destacking a layer, from a stacked layer palletload, with a layer destacking system, the method comprising: seating thedestacked layer on a layer seating platform, where the layer seatingplatform has a conveying surface with a conveyance traverse directionthat traverses the seated destacked layer off the layer seatingplatform; sensing, with a slip sheet detection sensor coupled to thelayer seating platform, a slip sheet in contact with the seateddestacked layer on at least one of an uppermost surface and a bottomsurface of the seated destacked layer; engaging, above the layer seatingplatform and with a slip sheet pickup removal mechanism extending atleast in part over the layer seating platform, the slip sheet contactingthe at least one of the uppermost surface and the bottom surface of theseated destacked layer; and receiving, with a controller communicablycoupled to the slip sheet detection sensor, a signal from the slip sheetdetection sensor identifying presence of the slip sheet; wherein thecontroller is operably connected to the slip sheet pickup removalmechanism so as to actuate the slip sheet pickup removal mechanismengaging the slip sheet contacting the at least one of the uppermostsurface and the bottom surface, and lifting the slip sheet effectingdischarge of the slip sheet off the layer seating platform based on thesignal.
 23. The method of claim 22, wherein the controller is configuredto determine, from the signal, the slip sheet contacting the at leastone of the uppermost surface and the bottom surface of the seateddestacked layer.
 24. The method of claim 22, wherein the slip sheetpickup removal mechanism has a pick head that engages an upper surfaceof the slip sheet.
 25. The method of claim 22, wherein the slip sheetdetection sensor is disposed to sense the slip sheet on the at least oneof the uppermost surface and the bottom surface of the seated destackedlayer.
 26. The method of claim 22, wherein the slip sheet detectionsensor is an electromagnetic beam sensor arranged so as to emit asensing beam in a direction that crosses a seating plane of theconveying surface so as to sense the slip sheet on the at least one ofthe uppermost surface and the bottom surface of the seated destackedlayer.
 27. The method of claim 22, wherein the slip sheet detectionsensor is an imaging sensor registering the slip sheet on the at leastone of the uppermost surface and the bottom surface of the seateddestacked layer in a direction crossing a seating plane of the seateddestacked layer seated on the conveying surface.
 28. The method of claim22, further comprising actuating a displacer, that is movably coupled tothe layer seating platform, in a direction aligned with the conveyancetraverse direction between an advanced position and a retracted positionthat displaces the seated destacked layer and the slip sheet on thebottom surface relative to each other stripping the seated destackedlayer and slip sheet from each other.